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IS 800:2007, , Indian Standard, GENERAL CONSTRUCTION IN, STEEL — CODE OF PRACTICE, , ( Third Revision), , ICS 77.140.01, , Q BIS 2007, , BUREAU, MA.NAK, , December 2007, , OF, BHAVAN,, , INDIAN, , STANDARDS, , 9 BAHADUR, SHAH, NEW DELHI 110002, , ZAFAR, , MARG, , Price Rs. 1130.!?!?

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Structural Engineering, , and Structural, , Sections Sectional Committee,, , CED 7, , FOREWORD, This Indian Standard (Third Revision) was adopted by the Bureau of Indian Standards, after the draft finalized, by the Structural Engineering and Structural Sections Sectional Committee had been approved by the Civil, Engineering Division Council., The steel economy programme was initiated by erstwhile Indian Standards Institution in the year 1950 with the, objective of achieving economy in the use of structural steel by establishing rational, efficient and optimum, standards for structural steel products and their use. IS 800: 1956 was the first in the series of Indian Standards, brought out under this programme. The standard was revised in 1962 and subsequently in 1984, incorporating, certain very importmt changes., IS 800 is the basic Code for general construction in steel structures and is the prime document for any structural, design and has influence on many other codes governing the design of other special steel structures, such as, towers, bridges, silos, chimneys, etc. Realising the necessity to update the standard to the state of the art of the, steel construction technology and economy, the current revision of the standard was undertaken. Consideration, has been given tO the de~elopments taking place in the country and abroad, and necessary modifications and, additions have been incorporated to make the standard more useful., The revised standard will enhance the confidence of designers, engineers, contractors, technical institutions,, professional bodies and the industry and will open a new era in safe and economic construction in steel., In this revision the following, , major modifications, , have been effected:, , a), , In view of’the development and production of new varieties of medium and high tensile structural steels, in the country, the scope of the standard has been modified permitting the use of any variety of structural, steel provided the relevant provisions of the standard are satisfied., , b), , The standard has made reference to the Indian Standards now available for rivets; bolts and other fasteners., , c), , The standard is based on limit state method, reflecting the latest developments, , and the state of the art., , The revision of the standard was based on a review carried out and the proposals framed by Indian Institute of, Technology Madras (IIT Madras). The project was supported by Institute of Steel Development and Growth, (INSDAG) Kolkata. There has been considerable contribution from INSDAG and IIT Madras, with assistance, from a number of academic, research, design and contracting institutes/organizations,, in the preparation of the, revised standard., In the formulation, AS-4 100-1998, , of this standard the following publications, , have also been considered:, , CAN/CSAS16.1-94, ENV [993-1-1:, 1992 Part 1-1, , Steel structures (second edition), Standards Australia (Standards Association of Australia),, Homebush, NSW 2140,, Structural use of steelwork in buildings:, Code of practice for design in simple and continuous construction: Hot rolled sections, British, Standards Institution, London., Limit states design of steel structures, Canadian Standards Association, Rexdale (Toronto),, Ontario, Canada M9W 1R3., Eurocode 3: Design of steel structures:, General rules and rules for buildings, , The composition, , of the Committee, , BS-5950-2000, Part 1, , responsible, , for the formulation, , of this standard is given in Annex J., , For the purpose of deciding whether a particular requirement of this standard, is complied with, the final value,, observed or calculated, expressing the result of a test or analysis, shall be rounded off in accordance with, IS 2:1960 ‘Rules for rounding off numerical values (revised)’. The number of significant places retained in the, rounded off value should be the same as that of the specified value in this standard.

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1S 800:2007, , Contents, , SECTION, 1.1, 1.2, 1.3, 1,4, 1.5, 1.6, 1.7, 1.8, , 1, , 1 GENERAL, , 1, 1, 1, 5, 11, 11, 11, 12, , scope, References, Terminology, Symbols, Units, Standard Dimensions, Form and Weight, Plans and Drawings, Convention for Member Axes, , 12, , SECTION 2 MATERIALS, 2.1, 2.2, 2.3, 2,4, 2.5, 2.6, 2.7, , SECTION 3 GENERAL, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 3.10, , DESIGN, , 15, , REQUIREMENTS, , 15, 15, 16, 16, 16, 17, 17, 20, 20, 21, , Basis for Design, Loads and Forces, Erection Loads, Temperature Effects, Load Combinations, Geometrical Properties, Classification of Cross-Sections, Maximum Effective Slenderness Ratio, Resistance to Horizontal Forces, Expansion Joints, , SECTION, 4.1, 4.2, 4,3, 4.4, 4.5, 4.6, SECTION, 5.1, 5.2, 5.3, 5.4, 5,5, 5.6, SECTION, 6.1, 6.2, 6.3, 6.4, , 12, 12, 12, 15, 15, 15, 15, , General, Structural Steel, Rivets, Bolts, Nuts and Washers, SteeI Casting, Welding Consumable, Other Materials, , 4 METHODS, , OF STRUCTURAL, , 22, , ANALYSIS, , 22, 22, 23, 24, 25, 26, , Methods of Determining Action Effects, Forms of Construction Assumed for Structural Analysis, Assumptions in Analysis, Elastic Analysis, Plastic Analysis, Frame Buckling Analysis, STATE DESIGN, , 27, , Basis for Design, Limit State Design, Actions, Strength, Factors Governing the Ultimate Strength, Limit State of Serviceability, , 27, 28, 28, 29, 30, 30, , 5 LIMIT, , 6 DESIGN, Tension, Design, Design, Design, , OF TENSION, , MEMBERS, , .,, , Members, Strength Due to Yielding of Gross Section, Strength Due to Rupture of Critical Section, Strength Due to Block Shear, i, , 32, 32, 32, 32, 33

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IS 800:2007, SECTION, 7.1, 7.2, 7.3, 7.4, 7.5, 7.6, 7.7, 7.8, , 7 DESIGN, , OF COMPRESS1ON, , 34, , MEMBERS, , Design Strength, Effective Length of Compression Members, Design Details, Column Bases, Angle Struts, Laced Columns, Battened Columns, Compression Members Composed of Two Components, , SECTION, 8.1, 8.2, 8.3, 8.4, 8.5, 8.6, 8.7, 8.8, 8.9, 8.10, SECTION, 9.1, 9.2, 9.3, SECTION, , 8 DESIGN, , OF MEMBERS, , SUBJECTED, , Back-to-Back, , TO BENDING, , SUBJECTED, , TO COMBINED, , 69, , FORCES, , 69, 69, 70, , General, Combined Shear and Bending, Combined Axial Force and Bending Moment, , 73, , 10 CONNECTIONS, , 73, 73, 74, 76, 78, 81, 82, 82, 82, 82, 83, 83, , 10.1 General, 10.2 Location Details of Fasteners, 10.3 Bearing Type Bolts, 10.4 Friction Grip Type Bolting, 10.5 Welds and Welding, 10.6 Design of Connections, 10.7 Minimum Design Action on Connection, 10.8 Intersections, 10.9 Choice of Fasteners, 10.10 Connection Components, 10.11 Analysis of a Bolt/Weld Group, 10.12 Lug Angles, SECTION, 11.1, 11.2, 11.3, 11.4, 11.5, 11.6, SECTION, 12.1, 12.2, 12.3, 12.4, 12.5, 12.6, 12.7, , 11 WORKING, , STRESS, , 52, 52, 52, 54, 59, 60, 63, 65, 69, 69, 69, , General, Design Strength in Bending (Flexure), Effective Length for Lateral Torsional Buckling, Shear, Stiffened Web Panels, Design of Beams and Plate Girders with Solid Webs, Stiffener Design, Box Girders, Purlins and Sheeting Rails (Girts), Bending in a Non-Principal Plane, 9 MEMBER, , 34, 35, 46, 46, 47, 48, 50, 52, , 84, , DESIGN, , 84, 84, 84, 85, 85, 86, , General, Tension Members, Compression Members, Members Subjected to Bending, Combined Stresses, Connections, 12 DESIGN AND DETAILING, , FOR EARTHQUAKE, , General, Load and Load Combinations, Response Reduction Factor, Connections, Joints and Fasteners, Columns, Storey Drift, Ordinary Concentrically Braced Frames (OCBF), ii, , LOADS, , 87, 87, 87, 87, 87, 87, 88, 88

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IS 8~0 :2007, 12.8 Special Concentrically, , 88, , Braced Frames (SCBF), , 12.9 Eccentrically Braced Frames (EBF), 1~. 10 Ordinav Moment Frames (OMF), , 89, , 12.11 Special Moment Frames (SMF), , 90, , 12.12 Column Bases, , 90, , SECTION, , 89, , 91, , 13 FATIGUE, , 13.1 General, 13.2 Design, , 91, 91, , 13.3 Detail Category, , 92, , 13.4 Fatigue Strength, , 93, 99, , 13.5 Fatigue Assessment, , 100, , 13.6 Necessity for Fatigue Assessment, SECTION, , 14 DESIGN ASSISTED, , 100, , BY TESTING, , 14.1 Need for Testing, , 100, , 14.2 Types of Test, , 101, , 14.3 Test Conditions, , 102, , 14.4 Test Loading, , 102, , 14.5 Criteria for Acceptance, , 103, , SECTION, , 15.1 General, 15.2 Requirements, SECTION, , 103, , 15 DURABILITY, , 103, 103, , for Durability, , 105, , 16 FIRE RESISTANCE, , 16.1 Requirements, , 105, , 16.2 Fire Resistance Level, , 105, , 16.3 Period of Structural Adequacy (PSA), , 106, , 16.4 Variation of Mechanical, , 106, , Properties of Steel with Temperature, , 16.5 Limiting Steel Temperature, , 106, , 16.6 Temperature, , Increase with Time in Protected Members, , 107, , 16.7 Temperature, , Increase with Time in Unprotected, , 108, , 16.8 Determination, 16.9 Three-Sided, , Members, , 108, , of PSA from a Single Test, , 108, , Fire Exposure Condition, , 16.10 Special Considerations, , 108, , 16.11 Fire Resistance Rating, , 109, , SECTION, , 17 FABRICATION, , 110, , AND ERECTION, , 110, , 17.1 General, 17.2 Fabrication, , 110, , Procedures, , 17.3 Assembly, , 112, , 17.4 Riveting, , 113, , 17.5 Bolting, , 113, , 17.6 Welding, , 113, , 17.7 Machining of Butts, Caps and Bases, , 113, , 17.8 Painting, , 113, , 17.9 Marking, , 114, , 17.10 Shop Erection, , 114, , 17.11 Packing, , 114, , 17.12 Inspection and Testing, , 114, , 17.13 Site Erection, , 114, , 17.14 Painting After Erection, , 116, , 17.16 Steelwork Tenders and Contracts, , 116, .., 111

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IS 800:2007, ANNEX A LIST OF REFERRED, , INDIAN, , 117, , STANDARDS, , METHODS, , 120, , B-1 Advanced Structural Analysis and Design, B-2 Second Order Elastic Analysis and Design, B-3 Frame Instability Analysis, , 120, 120, 120, , ANNEX B ANALYSIS, , ANNEX C DESIGN, C-1, C-2, C-3, C-4, C-5, , AND DESIGN, , AGAINST, , FLOOR, , 121, , VIBRATION, , 121, 121, 121, 122, 122, , General, Annoyance Criteria, Floor Frequency, Damping, Acceleration, , ANNEX D DETERMINATION, , OF EFFECTIVE, , LENGTH, , OF COLUMNS, , D-1 Method for Determining Effective Length of Columns in Frames, D-2 Method for Determining Effective Length for Stepped Columns (see 7.2.2), D-3 Effective Length for Double Stepped Columns, ANNEX E ELASTIC, , LATERAL, , TORSIONAL, , 128, 130, , ANNEX F CONNECTIONS, General, Beam Splices, Column Splice, Beam-to-Column, Column Bases, , 130, 130, 130, 131, 134, , Connections, , ANNEX G GENERAL RECOMMENDATIONS, AND CONTRACTS, G-1, G-2, G-3, G+4, G-5, G-6, G-7, G-8, G-9, , FOR STEELWORK, , General, Exchange of Information, Information Required by the Steelwork Designer, Information Required by Tenderer (If Not Also Designer), Detailing, Time Schedule, Procedure on Site, Inspection, Maintenance, , ANNEX H PLASTIC, , 122, 124, 124, 128, , BUCKLING, , E-1 Elastic Critical Moment, , F-1, F-2, F-3, F-4, F-5, , 122, , PROPERTIES, , TENDERS, , 135, 135, 135, 135, 136, 137, 137, 137, 137, 137, 138, , OF BEAMS, , iv

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. . . .... ., , -=, , IS 800:2007, , Indian Standard, GENERAL CONSTRUCTION IN, STEEL — CODE OF PRACTICE, ( Third Revision), 1.3.1 Accidental Loads — Loads due to explosion,, impact of vehicles, or other rare loads for which the, structure is considered to be vulnerable as per the user., , SECTION 1, GENERAL, 1.1 Scope, , 1.3.2 Accompanying Load — Live (imposed) load, acting along with leading imposed load but causing, lower actions and/or deflections., , 1.1.1 This standard applies to general construction, using hot rolled steel sections joined using riveting,, bolting and welding. Specific provisions for bridges,, , 1.3.3 Action Effect or Load Effect — The internal force,, axial, shear, bending or twisting moment, due to, external actions and temperature loads,, , chimneys, cranes, tanks, transmission line towers, bulk, storage structures, tubular structures, cold formed light, gauge steel sections, etc, are covered in separate, standards., , 1.3.4 Action — The primary cause for stress or, deformations in a structure such as dead, live, wind,, seismic or temperature loads., , 1.1.2 This standard gives only general guidance as regards, the various loads to be considered in design. For the actual, loads and load combinations to be used, reference may, be made to IS 875 for dead, live, snow and wind loads, and to IS 1893 (Part 1) for earthquake loads., , 1.3.5 Actual Length — The length between centre-tocentre of intersection points, with supporting members, or the cantilever length in the case of a free standing, member., , 1.1.3 Fabrication and erection requirements covered, in this standard are general and the minimum necessary, quality of material and workmanship consistent with, assumptions, in the design, rules. The actual, requirements may be further developed as per other, standards or the project specification,, the type of, structure and the method of construction., , 1.3.6 Beam — A member subjected, bending., , 1.3.7 Bearing Type Connection — A connection made, using bolts in ‘snug-tight’ condition, or rivets where, the load is transferred by bearing of bolts or rivets, against plate inside the bolt hole., , 1.1.4 For seismic design, recommendations, pertaining, to steel frames only are covered in this standard. For, more detailed information on seismic design of other, structural and non-structural, components,, refrence, should be made to IS 1893 (Part 1) and other special, publications on the subject., , 1.3.8 Braced Member — A member in which the, relative transverse displacement is effectively prevented, by bracing., 1.3.9 Brittle Cladding — Claddings, such as asbestos, cement sheets which get damaged before undergoing, considerable deformation., , 1.2 References, , 1.3.10 Buckling Load— The load at which an element,, a member or a structure as a whole, either collapses in, service or buckles in a load test and develops excessive, lateral (out of plane) deformation or instability., , The standards listed in Annex A contain provisions, which through reference, in this text, constitute, provisions of this standard. At the time of publication,, the editions indicated were valid. All standards are, subject to revision and parties to agreements based on, this standard are encouraged, to investigate, the, possibility of applying the most recent editions of the, standards indicated in Annex A., , 1.3.11 Buckling Strength or Resistance — Force or, moment, which a member can withstand without, buckling., 1.3.12 Bui/t-ap Section — A member fabricated by, interconnecting, more than one element to form a, compound section acting as a single member., , 1.3 Terminology, For the purpose of this standard,, definitions shall apply., , predominantly to, , the following, , 1.3.13 Camber- Intentionally introduced pre-curving, (usually upwards) in a system, member or any portion, 1

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IS 800:2007, of a member with respect to its chord. Frequently,, camber is introduced to compensate for deflections at, a specific level of loads., , 1.3.28 Detail Category — Designation, given to a, particular detail to indicate the S-N curve to be used in, fatigue assessment., , 1.3.14 Characteristic Load (Action) — The value of, specified load (action), above which not more than a, specified percentage (usually 5 percent) of samples of, corresponding load are expected to be encountered., , 1.3.29 Discontinuity — A sudden change, section, of a loaded member,, causing, concentration at the location., , 1.3.30 Ductility — It is the property of the material or, a structure indicating the extent to which it can deform, beyond the limit of yield deformation before failure or, fracture. The ratio of ultimate to yield deformation is, usually termed as ductility., , 1.3.15 Characteristic Yield/Ultimate Stress — The, minimum value of stress, below which not more than, a specified, percentage, (usually, 5 percent), of, corresponding stresses of samples tested are expected, to occur., , 1.3.31 Durability — It is the ability of a material to, resist deterioration over long periods of time., , 1.3.16 Column — A member in upright (vertical), position which supports a roof or floor system and, predominantly subjected to compression., , 1.3.32 Earthquake Loads — The inertia forces, produced in a structure due to the ground movement, during an earthquake., , 1.3.17 Compact Section —A cross-section, which can, develop plastic moment, but has inadequate plastic, rotation capacity needed for formation of a plastic, collapse mechanism of the member or structure., 1.3.18, between, , 1.3.33 Edge Distance — Distance from the centre of a, fastener hole to the nearest edge of an element, measured perpendicular, to the direction, of load, transfer., , Constant Stress Range — The amplitude, which the stress ranges, , under cyclic loading, , 1.3.34 Eflective Lateral Restraint — Restraint, that, produces sufficient resistance to prevent deformation, in the lateral direction., , is constant during the life of the structure or a structural, element., 1.3.19 Corrosion — An electrochemical, the surface of steel, leading to oxidation, 1.3.20 Crane Load — Horizontal, from cranes., , process over, of the metal., , 1.3.35 Effective Length — Actual length of a member, between points of effective restraint or effective, restraint and free end, multiplied by a factor to take, account of the end conditions in buckling strength, calculations., , and vertical loads, , 1.3.21 Cumulative Fatigue — Total damage, fatigue loading of varying stress ranges., , due to, , 1.3.36 Elastic Cladding — Claddings,, sheets, that can undergo considerable, without damage., , 1.3.22 Cut-o~Limit — The stress range, corresponding, to the particular detail, below which cyclic loading need, not be considered, in cumulative, fatigue damage, evaluation (corresponds to 108 numbers of cycles in, most cases)., , such as metal, deformation, , 1.3.37 Elastic Critical Moment —The elastic moment,, which initiates lateral-torsional buckling of a laterally, unsupported beam., 1.3.38 Elastic Design — Design, which assumes elastic, behaviour of materials throughout the service load, range., , of all, 1.3.23 Dead Loads — The self-weights, permanent constructions and installations including the, self-weight of all walls, partitions, floors, roofs, and, other permanent fixtures acting on a member., 1.3.24 Dejection — It is the deviation, standard position of a member or structure., , in crossa stress, , 1.3.39 Elastic Limit — It is the stress below which the, material regains its original size and shape when the, load is removed. In steel design, it is taken as the yield, stress., , from the, , 1.3.25 Design Life — Time period for which a structure, or a structural element is required to perform its, function without damage., , 1.3.40 End Distance — Distance from the centre of a, fastener hole to the edge of an element measured, parallel to the direction of load transfer., , 1.3.26 Design Load/Factored Load — A load value, ob~~ined by multiplying the characteristic load with a, load factor., , 1.3.41 Erection Loads — The actions (loads and, deformations) experienced by the structure exclusively, during erection., , 1.3.27 Design Spectrum — Frequency distribution of, the stress ranges from all the nominal loading events, during the design life (stress spectrum)., , 1.3.42 Erection Tolerance — Amount of deviation, related to the plumbness, alignment, and level of the, , 2

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. ... ., , —...,, , IS 800:2007, , 1.3.53 Flexural Stiffness — Stiffness of a member, against rotation as evaluated by the value of bending, deformation moment required to cause a unit rotation, while all other degrees of freedom of the joints of the, member except the rotated one are assumed to be, restrained., , element as a whole in the erected position. The, deviations are determined by considering the locations, of the ends of the element., 1.3.43 Exposed Surface Area to Mass Ratio — The, ratio of the surface area exposed to the fire (in mm2) to, the mass of steel (in kg)., , 1.3.54 Friction Type Connection — Connection, effected by using pre-tensioned, high strength bolts, where shear force transfer is due to mobilisation of, friction between the connected plates due to clamping, force developed at the interface of connected plates, by the bolt pre-tension., , NOTE — In the case of members with tire protection material, applied, the exposed surface area is to be taken as the internal, sur~acearea of the fire protection material., , 1.3.44 Fabrication Tolerance — Amount of deviation, allowed in the nominal dimensions and geometry in, fabrication activities, such as cutting to length, finishing, of ends, cutting of bevel angles, etc., , 1.3.55 Gauge — The spacing between adjacent parallel, lines of fasteners, transverse to the direction of load/, stress., , 1.3.45 Factor of Safety — The factor by which the yield, stress of the material of a member is divided to arrive, at the permissible, , stress in the material., , 1.3.56 Gravity Load — Loads, gravitational effects., , 1.3.46 Fatigue — Damage caused by repeated, fluctuations of stress, leading to progressive cmcking, of a structural element., , 1.3.59 Imposed (Live) Load — The load assumed to, be produced, by the intended, use or occupancy, including distributed, concentrated, impact, vibration, and snow loads but excluding, wind, earthquake and, temperature loads., , 1.3.49 Fire Exposure Condition, , Three-sidedfire exposure condition — Steel, in or in contact with a, floor or wall (at least, , 1.3.60 Instability — The phenomenon which disables, an element, member or a structure to carry further load, due to excessive deflection lateral to the direction of, loading and vanishing stiffness., , NOTES, 1 Three-sided fire exposure condition is to be considered, separately unless otherwise specified (see 16.10)., 2 Members with more than one face in contact with a, concrete or masonry floor or wall may be treated as, three-sided tire exposure., , b), , to, , 1.3.58 High Shear — High shear condition is caused, when the actual shear due to factored load is greater, than a certain fraction of design shear resistance, (see 9.2.2)., , 1.3.48 Fatigue Strength — The stress range for a, category of detail, depending upon the number of, cycles it is required to withstand during design life., , member incorporated, concrete or masonry, against one surface)., , due, , 1,3.57 GwssetPlate — The plate to which the members, intersecting at a joint are connected., , 1.3.47 Fatigue Loading — Set of nominal loading, events, cyclic in nature, described by the distribution, of the loads, their magnitudes, and the number of, applications in each nominal loading event., , a), , arising, , 1.3.61 Lateral Restraint for a Beam (see 1.3.34), , 1.3.62 Leading Imposed Load— Imposed load causing, higher action and/or deflection., , Four-sided jire exposure condition — Steel, 1.3.63 Limit State — Any limiting condition beyond, which the structure ceases to fulfil its intended function, (see also 1.3.86)., , member, which may be exposed to fire on all, sides., 1.3.50 Fire Protection System — The fire protection, material and its method of attachment to the steel, member., , 1.3.64 Live Load (see 1.3.59), , 1.3.65 Load — An externally applied force or action, (see also 1.3.4)., , 1.3.51 Fire Resistance — The ability of an element,, component or structure, to fulfil for a stated period of, time, the required stability, integrity, thermal insulation, and/or other expected performance, specified in a, standard fire test., , 1.3.66 Main Member — A structural member, which, is primarily responsible for carrying and distributing, the applied load or action., 1.3,67 Mill Tolerance — Amount of variation allowed, from the nominal dimensions, and geometry, with, respect to cross-sectional, area, non-parallelism, of, , 1.3.52 FireResistanceLevel —The fwe resistance grading, period for a structural element or system, in minutes,, which is required to be attained in the standard fire test., 3

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IS 800:2007, flanges, and out of straightness, such as sweep or, camber, in a product, as manufactured in a steel mill., , structures, members or connections that are nominally, identical (full scale) to the units tested., , 1.3.68 Normal Stress — Stress component, normal to the face, plane or section., , 1.3.82 Prying Force — Additional, tensile force, developed in a bolt as a result of the flexing of a, connection component such as a beam end plate or leg, of an angle., , acting, , 1.3,69 Partial Safety Factor — The factor normally, greater than unity by which either the loads (actions), are multiplied or the resistances are divided to obtain, the design values., , 1.3.83 Rotatiort — The change in angle at a joint, between the original orientation of two linear member, and their final position under Ioadlng., , 1.3.70 Period of Structural Adequacy under Fire ——, The time (t), in minutes, for the member to reach the, limit state of structural inadequacy in a standard fire, test., , 1.3.84 Secondary Member — Member which is, provided for overall stability and or for restraining the, main members from buckling or similar modes of, failure., , 1.3.71 Permissible S~rcss— When a structure is being, designed by the working stress method, the maximum, stress that is permitted to be experienced in elements,, members or structures under the nominal/service load, , 1.3.85 Semi-compact Section — Cross-section, which, can attain the yield moment, but not the plastic moment, before failure by plate buckling., 1.3.86 Serviceability .Lirnit State — A limit state of, acceptable service condition exceedence of which, causes serviceability failure., , (action)., 1.3.72 Pitch — The centre-to-centre distance between, individual fasteners in a line, in the direction of load/, stress., , 1.3.87 Shear Force — The inplane, transverse cross-section, of a straight, column or beam., , 1.3.73 Plastic Collapse — The failure stage at which, sufficient number of plastic hinges have formed due, to the loads (actions) in a structure leading to a failure, mechanism., , force at any, member of a, , 1.3.74 Plastic IMsi,gn — Design against the limit state, of plastic collapse., , 1.3.88 Shear Lag — The in plane shear deformation, effect by which concentrated forces tangential to the, surface of a plate gets distributed over the entire section, perpendicular to the load over a finite length of the, plate along the direction of the load., , 1.3.75 Plastic Hinge — A yielding zone with, significant inelastic rotation, which forms in a member,, , 1.3.89 Shear Stress — The stress component, parallel to a face, plane or cross-section., , when the plastic moment is reached at a section., , 1.3.90 Slender Section — Cross-section in which the, elements buckle locally before reaching yield moment., , 1.3.76 Plastic Mo~nent— Moment capacity of a crosssection when the entire cross-section, to bending moment., , acting, , has yielded due, , 1.3.91 Slenderness Ratio — The ratio of the effective, length of a member to the radius of gyration of the, cross-section about the axis under consideration., , which can, 1.3.77 Plastic Section — Cross-section,, develop a plastic hinge and sustain piastic moment over, sufficient plastic rotation required for formation of, plastic failure mechanism of the member or structure., , 1.3.92 Slip Resistance — Limit shear that can be, applied in a friction grip connection before slip occurs., , 1,3.78 Poisson’s Ratio — It is the absolute value of, the ratio of lateral strain to longitudinal strain under, uni-axial Ioading., , 1.3.93 S-N Curve —The curve defining the relationship, between the number of stress cycles to failure (N,c) at, a constant stress range (SC), during fatigue loading of, a structure., , 1.3.79 Proof Stress — The stress to which high strength, friction grip (HSFG) bolts are pre-tensioned., , 1.3.94 Snow Load — Load on a structure due to the, accumulation of snow and ice on surfaces such as roof., , 1.3,80 Proof Testing — The application of test loads, to a structure, sub-structure, member or connection to, ascertain the structural characteristics, of only that, specific unit., , The tightness of a bolt achieved, 1.3.95 Snug i’ight ——, by a few impacts of an impact wrench or by the full, effort of a person using a standard spanner., , Limit State — A limit state, 1.3.96 Stability, corresponding to the loss of static equilibrium of a, structure by excessive deflection transverse to the, direction of predominant loads., , 1.3.81 Prototype Testing — Testing of structure, substructure, members or connections, to ascertain the, structural characteristics of that class of structures, sub4

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IS 800:2007, 1.3.115 Transverse — Direction atong the stronger axes, of the cross-section of the member., , 1.3.97 Stackability — The ability of the fire protection, system to remain in place as the member deflects under, load during a fire test., , 1.3.116 Ultimate Limit State — The state which, if, exceeded can cause collapse of a part or the whole of, the structure., , 1.3.98 St~ffener— An element used to retain or prevent, the out-of-plane deformations of plates., 1.3.99 Strain — Deformation, angle., , 1.3.117 Ultimate Stress (see 1.3.113), , per unit length or unit, , 1.3.118 Wind Loads — Load experienced by member, or structure due to wind pressure acting on the surfaces., , of, 1.3.100 Strain Hardening — The phenomenon, increase in stress with increase in strain beyond, yielding., 1.3.101 Strength — Resistance, or buckling., , 1.3.119 Yield Stress — The characteristic stress of the, material in tension before the elastic limit of the, material is exceeded, as specified in the appropriate, Indian Stwdard, as listed in Table 1., , to failure by yielding, , 1.3.102 Strength Limir State — A limit state of collapse, or loss of structural integrity., , 1.4 Symbols, , 1.3.103 Stress — The internal force per unit area of, the original cross-section,, , Symbols used in this standard shall have the following, meanings with respect to the structure or member or, condition. unless otherwise defined elsewhere in this, Code., , 1.3.104 Stress Analysis —The analysis of the internal, force and stress condition in an element, member or, structure., , A, AC, A., AC,, A,, A,, A,,, A,O, , I.3.105 Stress Cycle Counting — Sum of individual, stress cycles from stress history arrived at using any, rational method., 1.3.106 Stress Range — Algebraic difference between, two extremes of stresses in a cycle of loading., 1.3.107 Stress Spectrum — Histogram of stress cycles, produced by a nominal loading event design spectrum,, during design life., , A,, , 1.3.108 Structural Adequacy for Fire — The ability of, the member to carry the test load exposed to the, standard fire test., , An,, , A,,C, , 1.3.109 Structural Analysis — The analysis of stress,, strain, and deflection characteristics of a structure., , An,, , 1.3.110 Strut — A compression, be oriented in any direction., , A,O, , member, which may, , 1.3.111 Sway — The lateral deflection, , of a frame., , A,,, , 1.3.112 Sway Member — A member in which the, transverse displacement of one end, relative to the other, is not effectively prevented., stress, 1.3.113 Tensile Stress — The characteristic, corresponding to rupture in tension, specified for the, grade of steel in the appropriate Indian Standard, as, listed in Table 1., 1.3.114 Test Load — The factored load, equivalent to, a specified load combination appropriate for the type, of test being performed., , 5, , — Area of cross-section, — Area at root of threads, — Effective cross-sectional, , area, — Reduced effective flange area, — Total flange area, — Gross cross-sectional area, — Gross cross-sectional area of flange, — Gross, cross-sectional, area of, outstanding (not connected) leg of a, member, — Net area of the total cross-section, — Net tensile cross-sectional area of bolt, — Net cross-sectional, area of the, connected leg of a member, — Net cross-sectional, area of each, flange, — Net, cross-sectional, area, of, outstanding (not connected) leg of a, member, — Nominal bearing area of bolt on any, plate, , A,, , — Cross-sectional, area of a bearing, (load carrying) stiffener in contact, with the flange, , A,, , — Tensile stress area, , A,,, , — Gross cross-sectional, at the shank, , At,, , — Gross sectional area in tension from, the centre of the hole to the toe of, the angle section/channel section, etc, (see 6.4) perpendicular to the line of, force, , area of a bolt

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IS 800:2007, , A,n, , Av, Av,, , A,,, , a, b, , — Net sectional area in tension from the, centre of the hole to the toe of, the angle perpendicular to the line, of force (see 6.4), — Shear area, , compression flange angles, plates or, tongue plates to the neutral axis, , — Gross cross-sectional, area in shear, along the line of transmitted force, (see 6.4), — Net cross-sectional, area in shear, along the line of transmitted force, (se: 6.4 ), — Larger and smaller projection of the, , al, , B, b, b,, , — Peak acceleration, — Unsupported, length, , b,, b,, b,,, b,, b,, b,, b., c, , — Panel zone depth in the beam-column, junction, — Modulus of elasticity for steel, , Fd, , of individual, elements being laced between lacing, points, , F., FO, , — Length of side of cap or base plate of, a column, — Outstand/width of the element, — Stiff bearing length, Stiffener bearing, — Effective width of flange, pair of bolts, — Width of the flange, , dP, , F cdw, , F,,,, F~, F,,,, , length, , be, , — Diameter of a bolt/ rivet hole, , E, E (~, E (20), E,, , slab base beyond, the rectangle, circumscribing, the, column,, respectively (see 7.4), , aO, , d,, dO, , — Width of flange as an internal element, — Width of flange outstand, — Panel zone width between column, flanges at beam-column junction, — Shear lag distance, , Ftesl, R, Ftest,s, FW, F,, FXd, , — Width of tension field, — Width of outstanding leg, — Centre-to-centre, longitudinal, — Coefficient, , f, f,, , of thermal expansion, , Cn,y,Cmz— Moment amplification, , factor about, , respective axes, c, Ch, , C,n, , c,, , D, d, d,, , f,, , — Spacing of transverse stiffener, — Moment amplification, factor for, braced member, — Moment reduction factor for lateral, torsional, calculation, , buckling, , — Moment amplification, sway frame, — Overall depth/diameter, , L, k., , strength, , J,c, factor, , — Modulus of elasticity of steel at T “C, — Modulus of elasticity of steel at 20”C, — Modulus of elasticity of the panel, material, — Buckling strength of un-stiffened, beam web under concentrated load, — Factored design load, — Normal force, — Minimum proof pretension in high, strength friction grip bolts., — Bearing capacity of load carrying, stiffener, — Stiffener force, — Stiffener buckling resistance, — Test load, , F lest, F,~,,,, — Load for acceptance test, F test, Mm — Minimum test load from the test to, , between, , distance of battens, cm, , — Nominal diameter of the pipe column, or the dimensions of the column in, the depth direction of the base plate, , for, , “&(, of the cross-, , .fipb, , section, — Depth of web, Nominal diameter, — Twice the clear distance from the, , J,,,, , failure, — Test load resistance, — Strength test load, — Design capacity of the web in bearing, — External load, force or reaction, — Buckling resistance of load carrying, web stiffener, — Actual normal stress range for the, detail category, — Frequency for a simply supported one, way system, -— Frequency of floor supported on steel, girder perpendicular to the joist, — Calculated stress due to axial force, at service load, — Permissible, bending, stress, in, compression at service load, — Permissible, compressive, stress at, service load, — Permissible bending stress in tension, at service load, — Permissible bearing stress of the bolt, at service load, — Permissible stress of the bolt in shear, at service load, , 6

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IS 800:2007, — 1permissible, 1,oad, — 1Permissible, , tensile stress at service, , tensile stress of the bolt, it service load, , — 1Permissible, stress of the weld at, service load, — Actual bending stress at service load, , f“, , ., , f, .W, fwj, f w“, fx, , — Actual stress of weld at service load, — Design stress of weld at service load, ., Nominal strength of fillet weld, , — Actual bending stress in compression, at service load, — Design bending compressive stress, , &, fy(n, fy(20), , corresponding to lateral buckling, — Actual bearing stress due to bending, at service load, — Actual bending stress in tension at, , f,,, f,,, f ym, , service load, — Permissible bending stress in column, base at service load, , f,,, , Actual axial compressive, service load, , f,,, , stress at, , — Elastic buckling stress of a column,, Euler buckling stress, — Design compressive stress, , f Yw, , — Extreme fibre compressive, stress, corresponding elastic lateral buckling, moment, — Equivalent stress at service load, — Fatigue stress range corresponding to, , g, , G, , h, IIb, , 5 x 10’ cycles of loading, — Equivalent constant amplitude stress, — Design normal fatigue strength, , hC, he, h,, hi, h,, h,, h,, , — Highest normal stress range, — Normal fatigue stress range, ., Normal stress in weld at service load, — Proof stress, — Actual bearing stress at service load, — Actual bearing stress in bending at, service load, — Bearing strength of the stiffeners, , I, , Applied shear stress in the panel, designed utilizing tension field action, , — Maximum longitudinal stress under, combined axial force and bending, — Characteristic yield stress, — Yield stress of steel at T ‘C, — Yield stress of steel at 20°C, — Characteristic yield stress of bolt, — Characteristic yield stress of flange, ., , Average yield stress as obtained from, test, , — Characteristic, yield, stress, of, connected plate, — Characteristic yield stress of stiffener, material, — Characteristic yield stress of the web, material, — Modulus of rigidity for steel, — Gauge length between centre of the, holes perpendicular, to the load, direction, acceleration due to gravity, — Depth of the section, — Total height from the base to the floor, level concerned, — Height of the column, — Effective thickness, — Cenre-to-centre distance of flanges, — Thickness of fire protection material, — Height of the lip, ., , Storey height, — Distance between shear centre of the, two flanges of a cross-section, — Moment of inertia of the member, about an axis perpendicular, plane of the frame, , — Frequency, — Actual shear stress in bolt at service, load, — Actual tensile stress at service load, , I fc, , If,, , — Actual tensile stress of the bolt at, service load, — Characteristic ultimate tensile stress, — Characteristic ultimate tensile stress, of the bolt, — Average, ultimate, stress of the, , I,, , to the, , — Moment of inertia of the compression, flange of the beam about the axis, parallel to the web, — Moment of inertia of the tension, flange of the beam about minor axis, — Moment, of inertia of a pair of, stiffener about the centre of the web,, or a single stiffener about the face of, the web, , 1,, I,., , material as obtained from test, — Characteristic ultimate tensile stress, of the connected plate, 7, , — Second moment of inertia, — Second moment of inertia of the, stiffener about the face of the element, perpendicular to the web

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IS 800:2007, , 1,, , IV, I,, K,, , KL, KL(r, , — Appropriate, effective, ratio of the section, — Effective slenderness, , KLJry, , L,, , 1,, , lw, M, , M,, MC,, , -, , M,, M,,, A’ldy, , — Shear buckling co-efficient, — Warping restraint factor, coefficient, , — Maximum distance from the restraint, , length for lateral torsional, , to the compression, flange at the, plastic hinge to an adjacent restraint, (limiting distance), , LO, , M~fi, M,,, , — Reduced effective moment, , M,,, , — Design piastic resistance of the flange, alone, , Mn,, , — Design, bending, strength, under, combined axial force and uniaxial, moment, , — Reduced plastic moment capacity of, the flange plate, , — Plastic, , bending, strength, under, axial force and the, uniaxial moment acting, moment, , capacity, , of the, , section, , in bolted, and welded members, taken as the, distance between outermost fasteners, in the end connection, or the length, of the end weld, measured along the, length of the member, , L., , — Design bending strength about the, major axis of the cross-section, , M,, , — Length of end connection, , —, , M&, , combined, respective, alone, , Actual length, unsupported length,, Length centre-to-centre, distance of, the intersecting members, Cantilever, length, , L LT, , moment, torsional, , — Design flexural strength, — Moment capacity of the section under, high shear, — Design bending strength about the, , M,~Y,M“~Z—Design, , Exposed surface area to mass ratio, , Effective, buckling, , — Bending moment, — Applied bending moment, — Elastic, critical, , minor axis of the cross-section, , Effective slenderness, ratio of the, laced column accounting for shear, deformation, , Regression, , — Length of the joint, — Length between points of lateral, support to the compression flange in, a beam, — Distance from bolt centre line to the, toe of fillet weld or to half the root, radius for a rolled section, — Length of weld, , slenderness, , effective, Actual, maximum, slenderness ratio of the laced column, , 0, , — Centre-to-centre, length, of the, supporting member, — Distance between prying force and, bolt centre line, — Grip length of bolts in a connection, , corresponding, to lateral, buckling of the beam, , — Effective slenderness, ratio of the, section about the major axis of the, section, , (1, K,, K,V, k—, k—, sm, L—, , 1,, , ratio of the, section about the minor axis of the, section, , KLlrz, , KL, r<, , lg, li, , column, — Reduction factor to account for the, high strength friction grip connection, bolts in over sized and slotted holes, — Effective length of the member, , K,, , KL, ——, r, , 1,, , — Warping constant, ., Moment of inertia about the minor, axis of the cross-section, — Moment of inertia about the major, axis of the cross-section, — Effective stiffness of the beam and, , Iw, , (“-), , 1, , — Transformed moment of inertia of the, one way system, (in terms of, equivalent, steel,, assuming, the, concrete flange of width equal to the, spacing of the beam to be effective), — St. Venant’s torsion constant, , [T, , — Length, , between, points of zero, moment (inflection) in the span, 8, , M,,, , — Moment, , M., , — Moments, , M@, MP~~, M~, M,, M,,, MY, , —, —, —, —, —, —, , in the beam, at the, intersection of the beam and column, centre lines, in the column, below the beam surfaces, , above and, , Plastic design strength, Plastic design strength of flanges only, Applied moment on the stiffener, Moment at service (working) load, Moment resistance, , of tension flange, , Factored applied moment about the, minor axis of the cross-section

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IS 800:2007, , M,,, , ., , M,, , — Factored applied moment about the, major axis of the cross-section, — Number of parallel planes of battens, , N, N,, N,, N,c, n, , R,, R,, R,,, RU, , Moment capacity of the stiffener, based on its elastic modulus, , — Design strength in tension, compression, — Axial force in the flange, . Numberof stress cycles, , or in, , r, rl, , — Number of bolts in the bolt group/, critical section, — Number, of effective, interfaces, offering frictional resistance to slip, — Number of shear planes with the, , r~, , threads intercepting the shear plane, in the bolted connection, , ry, , n,, , Number of shear planes without, threads intercepting the shear plane, in the bolted connection, , r,, , —, P, —, P<.., —, P,, P,,,Pdz—, , Factored applied axial force, , n,, n,, , P,, PMm, P,, P,, P,, P, , Q, , s, , s,, s,, so, , strength, , Design compression, strength, as, governed by flexural buckling about, the respective axis, , — Elastic Euler buckling load, — Minimum required strength for each, flange splice, — Required compressive strength, , s,, s“, s,, , — Actual compression at service load, — Yield strength of the cross-section, under axial compression, — Pitch length between centres of holes, , s,, , to the direction, , s,, T, , of the, , T,, T,,, T~, T4, , — Staggered, pitch length along the, direction of the load between lines of, the bolt holes (see Fig. 5), — Prying force, — Accidental load (Action), — Characteristic loads (Action), , Tdn, Tdb, , Q,, , — Design load (Action), — Permanent loads (Action), , Q,, , ., , Q,, Q,, Q,, , 9, , R, , R,, , — Ultimate strength of the member, room temperature, — Appropriate radius of gyration, , at, , — Minimum radius of gyration of the, individual, element, being laced, together, — Ratio of the design action on the, member under fire to the design, capacity, — Radius of gyration about the minor, axis (v-v) of angle section., — Radius of gyration about the minor, axis, — Radius of gyration about the major, axis, — Minimum, transverse, distance, between the centroid of the rivet or, bolt group or weld group, , Elastic buckling load, Design axial compressive, , parallel, load, , P,, , r““, , — Net shear in bolt group at bolt “i”, — Response reduction factor, — Flange shear resistance, , Variable loads (Action), — Shear stress at service load, — Ratio of the mean compressive, , T., T,, , stress, in the web (equal, to stress at, mid depth) to yield stress of the web;, reaction of the beam at support, , — Design strength of the member, room temperature, , — Original cross-sectional, test specimen, — Spring stiffness, , area of the, , — Ultimate strength, — Anchorage length, , of tension, along the compression flange, , field, , — Anchorage length of tension, along the tension flange, — Actual stiffener spacing, , field, , — Temperature, in degree, Factored tension, — Applied tension in bolt, , Celsius;, , — Thickness of compression flange, — Design strength under axial tension, — Yielding strength of gross section, under axial tension, — Rupture strength of net section under, axial tension, — Design strength of bolt under axial, tension;, Block shear strength at, end connection, — Externally applied tension, , T,b, , — Factored tension force of friction type, bolt, — Limiting temperature of the steel, — Nominal strength of bolt under axial, , T,d, , tension, — Design tension capacity, , T,, , at, , 9, , — Constant stress range, — Design strength

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IS 800:2007, Tndf, , ., , capacity, , of friction, , T,,,, , — Nominal tensile strength, type bolt, , of friction, , T,, t, , Actual tension under service load, — Thickness of element/angle, time in, minutes, — Thickness of flange, , $, $, 1pk, tq, t\, t,, t, ;, , ., , Thickness, — Thickness, — Thickness, , Vd, vdb, Vnb, v,,,, Vp, , member with respect, compression fibre, , —, , Elastic, section, modulus, of the, member with respect to extreme, tension flbre, , Zp, z“, , —, —, , Plastic section modulus, , Y,, , — Distance between point of application, of the load and shear centre of, the cross-section, , Y,, , — Co-ordinate, , of plate, of packing, of stiffener, , Thickness of base slab, — Effective throat thickness of welds, — Thickness of web,, — Factored applied shear force, , q, force, , in, , !-34, , — Critical shear strength corresponding, to web buckling, — Design shear strength, — Block shear strength, ., , Nominal shear strength of bolt, — Bearing capacity of bolt for friction, type connection, ., Plastic shear resistance under pure, , Xm, , — Nominal shear strength, — Nominal bearing strength of bolt, — Nominal shear capacity of a bolt, — Nominal shear capacity of bolt as, governed by slip in friction type, connection, , Xcr, , v,, V,h, v,,,, V,d,, , Transverse shear at service load, — Factored shear force in the bolt, , 6P, , w, , Wtf, .Xt, , z,, z,,, , 6, a,, , q, , Design shear capacity, — Design shear strength in friction type, bolt, — Factored, design, shear force of, friction bolts, — Applied transverse shear, , $, Y, x, , — Shear resistance in tension field, — Total load, — Uniform pressure from below on the, slab base due to axial compression, under the factored load, — Width of tension field, , Y., Y.10, x,,,, , ‘inb, , — Torsional index, — Elastic section modulus, — Elastic, , section, , modulus, , — Coefficient, –, , of thermal expansion, , Ratio of smaller to the larger bending, moment, at the ends of a beam, column, , for buckling under compression, , v,, v npb, vmb, v,,,, , v,, v,,, w, , Imperfection, factor for buckling, strength in columns and beams, , Lfyl ELI, — Equivalent uniform moment factor, for flexural buckling for y-y and z-z, axes respectively, —, Equivalent uniform moment factor, ILL,, for lateral torsional buckling, — Strength reduction factor to account, x, , shear, , v,,, , Contribution, to the plastic section, modulus of the total shear area of the, cross-section, , of the shear centre in, respect to centroid, , ct—, , Shear in batten plate, Factored frictional, shear, friction type connection, , to extreme, , z,.,, , ., , v,, vhf, , v,,, , Design tension, type bolt, , X“,, , ., , Strength reduction factor, X, at~,n, — Strength reduction factor to account, for lateral torsional, buckling, of, beams, — Storey deflection, — Horizontal deflection of the bottom, of storey due to combined gravity, and notional load, — Load amplification factor, — Horizontal deflection of the top of, storey due to combined gravity and, notional load, — Inclination of the tension field stress, in web, — Unit weight of steel, . Partial safety factor for load, — Partial safety factor for material, — Partial safety factor against yield, stress and buckling, — Partial safety factor against ultimate, stress, — Partial, safety factor for bolted, connection with bearing type bolts, — Partial, safety factor for bolted, connection, with High, Friction Grip bolts, , of the, 10, , Strength

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IS 800:2007, Yff,, , Ymft, Ymv, , — Partial safety factor for fatigue load, — Partial safety factor for fatigue, strength, — Partial safety factor against shear, , a), , Forces and loads, in kN, kN/m, kN/m2;, , b), , Unit mass, in kg/mJ;, , c), , Unit weight, in kN/ms;, , d), , Stresses and strengths,, MPa); and, , e), , Moments (bending,, , failure, , &, , — Partial safety factor for strength, weld, — Yield stress ratio (250 /~,) ‘n, , A, , — Non-dimensional, , 1’m., , slenderness, , For conversion of one system of units to another, system, IS 786 (Supplement) may be referred., 1.6 Standard, , =, , :T, , L,,r, , P, P,, P,, /’4, , e, , P, ‘r, Tb, T*b, rCr,e, 7,, ‘r f, Max, , ‘rfd, ‘rf., ‘r,, v, , r, , — Elastic buckling load factor, — Equivalent slenderness ratio, — Non-dimensional, lateral bending, — Elastic buckling, , Dimensions,, , Form and Weight, , The dimensions, form, weight, tolerances of all rolled, shapes, all rivets, bolts, nuts, studs, and welds and other, members used in any steel structure shall conform to, IS 808 and IS 1852, wherever applicable., , w, , A,,, , etc), in kNm., , ratio =, , a, , @ii7FE., , of, , in N/mm* (MN/m2 or, , slenderness ratio in, , 1.7 Plans and Drawings, , load factor of each, , 1.7.1 Plans, drawings and stress sheet shall be prepared, according to IS 8000 (Parts 1 to 4), IS 8976 and IS 962., , storey, — Poisson’s ratio, — Correction factor, — Coefficient of friction (slip factor), — Capacity reduction factor, , 1.7.1.1 Plans, The plans (design drawings) shall show the sizes,, sections, and the relative locations of the various, members. Floor levels, column centres, and offsets, shall be dimensioned. Plans shall be drawn to a scale, large enough to convey the information adequately., Plans shall indicate the type of construction, to be, employed; and shall be supplemented by such data on, the assumed loads, shears, moments and axial forces, to be resisted by all members and their connections, as, may be required for the proper preparation of shop, drawings. Any special precaution to be taken in the, erection of structure, from the design consideration, shall also be indicated in the drawing., , — Ratio of the rotation at the hinge point, to the relative elastic rotation of the, far end of the beam segment, containing plastic hinge, — Unit mass of steel, — Actual shear stress range for the detail, category, — Buckling shear stress, — Permissible shear stress at the service, load, — Elastic critical shear stress, , 1.7.1.2 Shop drawings, Shop drawings,, giving complete, information, necessary for the fabrication of the component parts, of the structure including the location, type, size,, length and detail of all welds and fasteners shall be, prepared in advance of the actual fabrication. They, shall clearly distinguish between shop and field rivets,, bolts and welds. For additional information, to be, included on drawings for designs based on the use of, welding, reference shall be made to appropriate Indian, Standards., Shop drawings, shall be made in, conformity with IS 962. A marking diagram allotting, distinct identification marks to each separate part of, steel work shall be prepared. The diagram shall be, sufficient to ensure convenient assembly and erection, at site., , — Fatigue shear stress range, — Highest shear stress range, — Design shear fatigue strength, — Fatigue shear stress range at N~Ccycle, for the detail category, — Actual shear stress at service load, — Ratio of the moments at the ends of, the laterally unsupported length of, a beam, — Frame buckling load factor, , NOTE — The subscripts y, : denote the y-y and Z-Zaxes of the, section, respectively. For symmetrical sections, y-y denotes the, minor principal axis whilst z-z denotes the major principal axis, (see 1.8)., , 1.7.2 Symbols used for welding on plans and shop, drawings shall be according to IS 813., , 1.5 Units, For the purpose of design calculations, units are recommended:, , the following, , 11

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IS 800:2007, , 1.8 Convention, , for Member, , Unless otherwise, specified, convention, member axes is as follows (see Fig. l):, a), , x-.x along the member., , b), , y-y an axis of the cross-section., , c), , d), , 1), , perpendicular, , 2), , perpendicular, angle section., , Z-Z, , 2.2.3.1 Steel that is not supported by mill test result, may be used only in unimportant members and details,, where their properties such as ductility and weldability, would not affect the performance requirements of the, members and the structure as a whole., , Axes, used, , for, , However, such steels may be used in structural system, after confirming, their quality by carrying, out, appropriate, tests in accordance, with the method, specified in IS 1608., , to the flanges, and, to the smaller, , leg in an, , an axis of the cross-section, , 2.2.4 Properties, , 1), , axis parallel to flanges, and, , 2), , axis parallel, section., , to smaller, , The properties of structural steel for use in design, may, be taken as given in 2.2.4.1 and 2.2.4.2., , leg in angle, , 2.2.4.1, Physical, properties, of structural, irrespective of its grade may be taken as:, , u-u major axis (when it does not coincide with, z-z axis)., , e), , v-v minor axis (when it does not coincide with, y-y axis)., SECTION 2, MATERIALS, , a), , Unit mass of steel, p = 7850 kg/m~, , b), , Modulus, (MPa), , c), , Poisson ratio, p = 0.3, , d), , Modulus of rigidity, G = 0.769 x 10s N/mm2, (MPa), , e), , Co-efficient, 10’ /“c, , 2.1 General, The material properties, given in this section are, nominal values, to be accepted as characteristic values, in design calculations., 2.2 Structural, , of elasticity, E = 2.0 x 10s N/mm2, , of thermal expansion, , cx.= 12 x, , 2.2.4.2 Mechanical properties of structural steel, The principaI mechanical properties of the structural, steel important in design are the yield stress, fy; the, tensile or ultimate stress, fu; the maximum percent, elongation on a standard gauge length and notch, toughness., Except for notch toughness, the other, properties are determined by conducting tensile tests, on samples cut from the plates, sections, etc, in, accordance with IS 1608. Commonly used properties, for the common, steel products, of different, specifications are summarized in Table 1., , Steel, , 2.2.1 The provisions in this section are applicable to, the steels commonly used in steel construction, namely,, structural mild steel and high tensile structural steel., 2.2.2 All the structural, steel used in general, construction, coming under the purview of this standard, shall before fabrication conform to IS 2062., 2.2.3 Structural steel other than those specified in 2.2.2, may also be used provided that the permissible stresses, and other design provisions are suitably modified and, the steel is also suitable for the type of fabrication, adopted., , 2.3 Rivets, , i;, I, , 2.3.1 Rivets, , shall, , be manufactured, , ~Y, , Ziz, ----- ,------, , steel, , y’, , Y!, , ., , i, i, i, , ‘Y, , iY, I, , FIG. 1 AXM OF MEMBERS, 12, , from, , steel

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IS 800:2007, Table 1 Tensile Properties, , of Structural, , Steel Products, , (Clauses 1.3.113, 1.3.119 and 2.2.4.2), Properties, , Indian Grade/Classification, sl, No. Standard, , i), , {, , ii) lS 814, , [, , iv) IS 1367, (Part 3), , (4), , (5), , (6), , 280, 250, 2Z0, , 270-410, 270-370, 270-350, , —, 28, 32, 35, , EX40XX, Ex4 ] XX, EX42XX, IZX43XX, EX44XX, , 330, 330, 330, 330, 330, , 410-540, 410-540, 410-540, 410-540, 410-540, , 16, 20, 22, 24, 24, , EX50XX, IZX5Ixx, F,X52XX, EX53XX, EX54XX, EX55XX, EX56XX, , 360, 360, 360, 360, 360, 360, 360, , 510-610, 510-610, 510-610, 510-610, 510-610, 5IO-61O, 510-610, , 16, 18, 18, 20, 20, 20, 20, , o, , —, , —, , D, DI), EDD, , —, , 240-400, 260-390, 260-380, , o, D, DD, EDD, , ls 513, , iii) IS 1079, , Ultimate Tensile Stress, MPa. Min, , (3), , (2), , (1), , 7, , {, , i, , [, , 3.6, 4.6, 4.8, 5.6, 5.8, 6.8, 8.8 (d< 16 mm), 8.8 (d> 16 mm), 9.8, 10.9, 12.9, , Min, , —, 640 ‘), 660 ‘), 720 ‘), 940 ‘), 1 100’), 200, 220, 230, 250, 270, 280, 320, 350, 370, , 1, 1A, 2, 2A, 3, 3A, 4, 5, 6, , V) IS 1875, , Elongation,, Percent,, , Yield Stress, MI%, Min, , —, 25, 28, 32, , 330, 400, 420, 500, 520, 600, 800, 830, 900, 1040, 1220, , 25, 22, —., 20, , 370, 410, 430, 460, 490, 540, 620, 710, 740, , 26, 25, 24, 22, 21, 20, 15, 13, 10, , 360-440, 410-500, , 26, 23, , —, —, , 12, 12, 10, 9, 8, , dort, , r, vi), , s, 37, S, 42, , IS 1990, , >20, 200, 240, , s 20, 220, 250, , ‘, , /, , vii) 1S2002, , {, , 1, 2, 3, , s16, , 235, 265, 290, , 225, 255, 285, , t, A, , t, , t, A, \, >16 and >40 and >60 and >100 and, <350, <100, s60, S40, 215, 245, 280, , 13, , 200, 215, 255, , 185, 200, 230, , v, >100, and, <350, 360-480 360-480 350-480, 410-530 410-530 400-530, 460-580 450-570 440-570, f, <60, , >60 and, <1oo, , <60, , 24, 22, 21, , \, , >60, and, S350, 23, 21, 20

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IS 800:2007, Table 1 (Concluded), SI, No., , (1), , Properties, , Grade/Classification, , Indian, Standard, , Yield Stress, MPa, Min, , UltimateTensile Stress, MPa, Min, , Elongation,, Pereent, Min, , (4), , (5), , (6), , 290, 410, 410, 410, 440, 490, 540, 570, 590, , 23, 23, 23, 23, 22, 22, 20, 20, 20, , (3), , (2), , dort, , viii), , E 165 (Fe 290), E250(Fe410W)A, E250(Fe 410 W)B, E250(Fe 410 W)C, E 300 (Fe 440), E 350 (Fe 490), E 410 (Fe 540), E 450 (Fe 570) D, E 450 (Fe 590) E, , IS 2062, , ~———l, <20, , 20-40, , >40, , 165, 250, 250, 250, 300, 350, 410, 450, 450, , 165, 240, 240, 240, 290, 330, 390, 430, 430, , 165, 230, 230, 230, 280, 320, 380, 420, 420, , \, dorr, , ix), , 1, 11, 11[, , 1s 3039, , {, , ~), , xi), , IS 6240, , 220, 235, , 400-490, 400-490, , 235, , 400-490, , 22, 22, , 350-450, , 25, , Grade 2, , 245, , 360-450, , 34, , f Annealed Condition, , 160, , 330-410, , 30, , As-Drawn Condition, , I90, , 410-490, , 20, , HFC 210/CDS, 2! OIERW21O, , 210, , 330, , 20, , HFC 240/CDS, 2401ERW240, , 240, , 410, , 18, , 310, , 450, , 15, , {, , [, {, , HFC 3 10/CDS, , [ 3Io/ERw31 o, , xiii), , 22, , 240, , Is 7557, , IS 9295, , >25 ands 50, , 230, 235, 235, , Grade 1, , t, , xii), , s 25, , 1S 10748, , {, , 1, , 170, , 290, , 30, , 2, , 210, , 330, , 28, , 3, , 240, , 410, , 25, , 4, , 275, , 430, , 20, , 5, , 310, , 490, , 15, , NOTES, 1 Percent of elongation shall be taken over the gauge length 5.65 &, , where So= Original cross-sectional area of the test specimen., , 2 Abbreviations: O = Ordinary, D = Drawing, DD = Deep Drawing, EDD = Extra Deep Drawing., I) Stress at 0.2 percent non-proportional elongation, Min., , 14

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IS 800:2007, construction and use and have adequate resistance to, certain expected accidental loads and tire. Structure, should be stable and have alternate load paths to prevent, disproportionate, overall collapse under accidental, loading., , conforming, to IS 7557., They may also be, manufactured, from steel conforming, to IS 2062, provided that the steel meets the requirements given, in IS 1148., 2,3.2 Rivets shall conform to IS 1929 and IS 2155 as, appropriate., , 3.1.2 Methods of Design, , 2.3.3 High Tensile Steel Rivets, , 3.1.2.1 Structure and its elements shall normally, be, , High tensile steel rivets, shall be manufactured, steel conforming to IS 1149., 2.4, , designed by the limit state method. Account should be, taken of accepted theories, experimental information, and experience and the need to design for dumbi]ity., Calculations alone may not produce Safe, serviceable, and durable structures. Suitable materials, quality, control, adequate detailing and good supervision are, equally important., , from, , Bolts, Nuts and Washers, , Bolts, nuts and washers shall conform as appropriate, to IS 1363 (Parts 1 to 3), IS 1364 (Parts 1 to 5), IS 1367, (Parts 1 to 20), IS 3640, IS 3757, IS 4000, IS 5369,, IS 5370, IS 5372, IS 5374, IS 5624, IS 6610, IS 6623,, IS 6639, and IS 6649. The recommendations in IS 4000, shall be followed., , 3.1.2.2 Where the limit states method cannot be, conveniently adopted; the working stress design (sef~, Section 11) may be used., 3.1.3 Design Process, , 2.5 Steel Casting, , Structural design, including design for durability,, construction and use should be considered as a whole., The realization, of design objectives, requires, compliance, with clearly defined, standards, for, materials,, fabrication,, erection, and in-service, maintenance., , Steel casting shall conform to IS 1030 or IS 2708., 2.6 Welding Consumable, 2.6.1 Covered electrodes, IS 1395, as appropriate., , shall conform, , 2.6.2 Filler rods and wires, conform to IS 1278., , to IS 814 or, , for gas welding, , shall, 3.2 Loads and Forces, 3.2.1 For the purpose of designing, any element,, member or a structure, the following loads (actions), and their effects shall be taken into account, where, applicable, with partial safety factors find combinations, (see 5.3.3):, , 2.6.3 The supply of solid filler wires for submerged, arc welding of structural, steels shall conform to, IS 1387., 2.6.4 The bare wire electrodes for submerged arc, welding shall conform to IS 7280. The combination, of wire and flux shall satisfy the requirements, of, IS 3613., 2.6.5 Filler rods and bare electrodes for gas shielded, metal arc welding shall conform to IS 6419 and, IS 6560, as appropriate., , a), , Dead loads;, , b), , Imposed loads (live load, crane load, snow, load, dust load, wave load, earth pressures,, etc);, , c), , Wind loads;, , d), , Earthquake, , loads;, , 2.7 Other Materials, , e), , Erection loads;, , Other materials used in association with structural steel, work shall conform to appropriate Indian Standards., , t], , Accidental loads such as those due to blast,, impact of vehicles, etc; and, , g), , Secondary, effects due to contraction, or, expansion, resulting, from temperature, changes,, differential, settlements, of the, structure as a whole or of its components,, eccentric, connections,, rigidity of joints, differing from design assumptions., , GENERAL, , SECTION 3, DESIGN REQUIREMENTS, , 3.1 Basis for Design, 3.1.1 Design Objective, , 3.2.1.1 Dead loads should be assumed, specified in 1S 875 (Part 1)., , The objective of design is the achievement, of an, acceptable probability that structures will perform, satisfactorily for the intended purpose duriug the design, life. With an appropriate degree of safety, they should, sustain all the loads and deformations,, during, , in design as, , 3.2.1.2 Imposed loads for different types of occupancy, and function, of structures, shall be taken as, recommended in IS 875 (Part 2). Imposed loads arising, 15

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IS 800:2007, from equipment, such as cranes and machines should, be assumed in design as per manufacturers/suppliers, data (see 3.5.4)., Snow load shall be taken as per, IS 875 (Part 4)., , 3,5 Load Combinations, 3.5.1 Load combinations for design purposes shall be, those that produce maximum forces and effects and, consequently, maximum stresses and deformations., The following combination of loads with appropriate, partial safety factors (see Table 4) maybe considered., , 3.2.1.3 Wind loads on structures shall be taken as per, the recommendations, of IS 875 (Part 3)., 3.2.1.4 Earthquake loads shall be assumed as per the, recommendations, of IS 1893 (Part 1)., , a), , Dead load + imposed load,, , b), , 3.2.1.5 The erection loads and temperature effects shall, be considered as specified in 3.3 and 3.4 respectively., , Dead load + imposed, earthquake load,, , c), , Dead load + wind or earthquake, , d), , Dead load+, , 3.3 Erection, , Loads, , + wind, , or, , load, and, , erection load., , NOTE — In the case of structures supporting crmres, imposed, loads shall include the crane effects as given in 3.5.4., , All loads required to be carried by the structure or any, part of it due to storage or positioning of construction, material and erection equipment, including all loads, due to operation of such equipment shall be considered, as erection loads. Proper provision shall be made,, including temporary bracings, to take care of all stresses, developed during erection. Dead load, wind load and, also such parts of the live load as would be imposed, on the stricture during the period of erection shall be, taken as acting together with the erection loads. The, structure as a whole and all parts of the structure in, conjunction, with the temporary bracings shall be, capable of sustaining these loads during erection., 3.4 Temperature, , load, , 3.5.2 Wind load and earthquake loads shall not be, assumed to act simultaneously. The effect of each shall, be considered separately., 3,5.3 The effect of cranes to be considered under, imposed loads shall include the vertical loads,, eccentricity, effects induced by the vertical loads,, impact factors, lateral (surge) and longitudinal, (horizontal) thrusts, not acting simultaneously, across, and along the crane rail, respectively, [see 1S 875, (Part 2)]., 3.5.4 The crane, considered shall, the absence of, combinations, provisions in IS, , Effects, , 3.4.1 Expansion and contraction due to changes in, temperature of the members and elements of a structure, shall be considered and adequate provision made for, such effect., 3.4.2 The temperature, range varies for different, localities and under different diurnal and seasonal, conditions. The absolute maximum and minimum, temperatures,, which may be expected in different, localities of the country, may be obtained from the, Indian Metrological Department and used in assessing, the maximum variations of temperature, for which, provision for expansion and contraction has to be made, in the structure., 3.4.3 The range of variation in temperature of the, building materials may be appreciably greater or lesser, than the variation of air temperature and is influenced, by the condition of exposure and the rate at which the, materials composing the structure absorb or radiate, heat. This difference in temperature variations of the, material and air shall be given due consideration. The, effect of differential temperature within an element or, member, due to part exposure to direct sunlight shall, also be considered., , loads and their combinations to be, be as indicated by the customer. In, any specific indications,, the load, shall be in accordance, with the, 875 (Part 2) or as given below:, , a), , Vertical loads with full impact from one, loaded crane or two cranes in case of tandem, operation, together with vertical loads without, impact from as many loaded cranes as may, be positioned for maximum effect, along with, maximum horizontal thrust from one crane, only or two in case of tandem operation;, , b), , Loads as specified in 3.5.4(a), subject to, cranes in maximum of any two bays of the, building cross-section shaIl be considered for, multi-bay multi-crane gantries;, , c), , The longitudinal thrust on a crane track rail, shall be considered for a maximum of two, loaded cranes on the track; and, , d), , Lateral thrust (surge) and longitudinal thrust, acting across and along the crane rail, respectively,, shall be assumed not to act, simultaneously. The effect of each force, shall, however be investigated separately., , 3.5.5 While investigating, the effect of earthquake, forces, the resulting effect from dead loads of all cranes, parked in each bay, positioned to cause maximum effect, shall be considered., , 3.4.4 The co-efficient of thermal expansion for steel is, as given in 2.2.4 .l(e)., , 16

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‘“”” —–-—~, , IS 800:2007, shall be less than that specified under Class 1, (Plastic), in Table 2., , 3.5.6 The crane runway girders supporting bumpers, shall be checked for bumper impact loads also, as, specified by the manufacturers., , b), , 3.5.7 Stresses developed due to secondary effects such, as handling; erection, temperature and settlement of, foundations, if any, shall be appropriately added to the, stresses calculated from the combination of loads stated, in 3.5.1, with appropriate partial safety factors., 3.6 Geometrical, , Properties, , 3.6.1 General, , c), , The geometrical, properties, of the gross and the, effective cross-sections of a member or part thereof,, shall be calculated on the following basis:, a), , The properties of the gross cross-section shall, be calculated from the specified size of the, member or part thereof, or read from, appr~priate tablet, , b), , The properties of the effective cross-section, shall be calculated by deducting from the area, of the gross cross-section, the following:, 1), , The sectional area in excess of effective, plate width, in case of slender sections, (see 3.7.2)., , 2), , The sectional areas of all holes in the section, except for parts in compression. In case of, punched holes, hole size 2 mm in excess, of the actual diameter may be deducted., , 3.7 Classification, , d), , of Cross-Sections, , — Cross-sections,, , which, , Class 3 (Semi-compact) — Cross-sections,, in which the extreme fiber in compression can, reach yield stress, but cannot develop the, plastic moment of resistance, due to local, buckling. The width to thickness ratio of plate, elements shall be less than that specified under, Class 3 (Semi-compact), but greater than that, specified under Class 2 (Compact), in Table 2., Class 4 (Slender) — Cross-sections in which, the elements buckle locally even before, reaching yield stress. The width to thickness, ratio of plate elements shall be greater than, that specified under Class 3 (Semi-compact),, in Table 2. In such cases, the effective sections, for design shall be calculated, either by, following the provisions of IS 801 to account, for the post-local-buckling, strength or by, deducting width of the compression, plate, element in excess of the semi-compact section, limit., , When different elements of a cross-section fall under, different classes, the section shall be classified as, governed by the most critical element., , 3.7.1 Plate elements of a cross-section, may buckle, locally due to compressive stresses. The local buckling, can be avoided before the limit state is achieved by, limiting the width to thickness ratio of each element, of a cross-section subjected to compression due to axial, force, moment or shear., , The maximum value of limiting, ratios of elements for different, sections are given in Table 2., , width to thickness, classifications, of, , 3.7,3 Types of Elements, , 3.7.1.1 When plastic analysis is used, the members ihall, be capable of forming plastic hinges with sufficient, rotation capacity (ductility) without local buckling, to, enable the redistribution of bending moment required, before formation of the failure mechanism., 3.7.1.2 When elastic analysis is used, the member shall, be capable of developing, the yield stress under, compression without local buckling., , a), , Internal elements — These, , b), , Outside elements or outstands – These are, elements attached along only one of the, longitudinal edges to an adjacent element, the, other edge being free to displace out of plane,, for example flange overhang of an I-section,, stem of T-section and legs of an angle section., , c), , Tapered elements — These maybe treated as, flat elements having average thickness as, defined in SP 6 (Part 1)., , 3.7.2 On basis of the above, four classes of sections, are defined as follows:, a), , Class 2 (Compact), , can develop plastic moment of resistance, but, have inadequate, plastic hinge rotation, capacity for formation of plastic mechanism,, due to local buckling. The width to thickness, ratio of plate elements shall be less than that, specified under Class 2 (Compact), but greater, than that specified under Class 1 (Plastic), in, Table 2., , Class 1 (Plastic) — Cross-sections, which, can develop plastic hinges and have the, rotation capacity required for failure of the, structure by formation of plastic mechanism., The width to thickness ratio of plate elements, 17, , are elements, attached along both longitudinal, edges to, other elements or to longitudinal stiffeners, connected at suitable intervals to transverse, stiffeners, for example, web of I-section and, flanges and web of box section.

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Table 2 Limiting, , Width to Thickness, , Ratio, , (Clauses 3.’7.2 and 3.7.4), .—, Compression Element, , Ratio, , Class of Section, Class 1, Plastic, , (1), )utstandirig element of, compressionflange, , Class3, Semi-compact, , Class’2, Compact, , (2), , (3), , (4), , (5), , b/t~, , 9.4&, , 10.5s, , 15.7E, , b/If, , 8.4&, , 9.4&, , 13.6s, , b/ tf, , 29.3s, , 33.5 &, , P, , b/ ff, C2YCw, Ifrl is negative:, Webof an 1,, 1 or box, iwtion, , 84&, , If r, is positive :, , 105s, , 126z, , 105.0 &, , dkq, , Generally, , t--, , 42s, , Not applicable, , 84E, , 1+<, , 126.0&, , 1+~, , 105$OC, —, 1+1.5~, , 1+ 2r*, , but s 42E, , dk+, , but <426, , but s 42.s, Axial compression, Webof a channel, 4ngle, compression due to bending (Both criteria should, )e satisfied), $ingle angle, or double angles with the components, ;eparated, axial compression (All three criteria should be, ;atistied), , 42c, , Not applicable, , dtw, , L//t., b/t, d/t, , 42s, , 42c, , 9.4&, 9.4 &, , lo.5&, 10.56, , I, , 15.7E, 15.7&, , b/t, (b?;)/t, , I, , 42E, , I, , 15.7&, 15.7.$, 25z, , I, , 15.7E, , Not applicable, , lrtstanding leg of an angle in contact back-to-back in a, louble angle member, , d/t, , outstanding leg of an angle with its back in continuous, :ontact with another component, , dlt, , 9.4&, , 10.5C, , 15.7&, , $tem of a T-section, rolled or cut from a rolled I-or H;ection, , D/t~, , 8.4&, , 9.4.?, , 18.9e, , hular hollow tube, including welded tube subjected to:, a) moment, b) axial compression, , I, , D/f, , I, , D/t, , I, , 9.4s, , 42.?, , I, , I, , 10.5s, , 52.?, , Not applicable, , ], , 146.#, , I, , 88/, , NOTES, 1 Elements which exceed semi-compact limits are to be taken as of slender cross-section., 26= (250 /~) ’n., 3 Webs shall be checked for shear buckling in accordance with 8,4.2 when d/t> 67E, where, b is the width of the element (may be, taken as clear distance between lateral supports or between lateral support and free edge, as appropriate), t is the thickness of, element, d is the depth of the web, D is the outer diameter of the element (see Fig. 2,3.7.3 and 3.7.4)., 4 Different elements of a cross-section can be in different classes. In such cases the section is classified based on the least, favorable classification., 5 The stress ratio r, and r~are defined as:, r, = Actual average axial stress (negative if tensile), Design compressive stress of web alone, r2= Actual average axial stress (negative if tensile), Design compressive stress of ovedl section, , 18

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——, , IS 800:2007, The design of slender compression element (Class 4), considering the strength beyond elastic local buckling, of element is outside the scope of this standard., Reference may be made to IS 801 for such design, provisions. The design of slender web elements may, be made as given in 8.2.1.1 for flexure and 8.4.2.2 for, shear,, tf, , Compound, (see Fig. 2), , 3.7.4, , Elements, , in Built-up, , In case of compound elements consisting of two or, more elements bolted or welded together, the limiting, width to thickness ratios as given in Table 2 should be, considered on basis of the following:, , tf, , l-=---i, , CIEiEu m, r, , tw, , d, , tw, , D, , h, , d, , L, , D, , d, , b--, , L-d, , b, , ROLLEDBEAMS, ANDCOLUMNS, , ROLLED, CHANNELS, , RECTANGULAR, HOLLOW, SECTIONS, , CIRCULAR, HOLLOW, SECTIONS, , r%?, r-f, d, , ~t, , T, , SINGLEANGLES, , TEES, , DOUBLEANGLES, (BACKTO BACK), , t,, 1, , t,, , rbl, , d, , l!, , l---u, , T, tw, , BUILT-UP, SECTIONS, , be, --ml, , b,, , ‘f, +, , d, , L, , Section, , ,t, , T, , COMPOUNDELEMENTS, , bi— Internal Element Width, b, — External Element Width, FIG. 2 DIMENSIONSOF SECTIONS, 19

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IS 800:2007, a), , Outstanding width ofcompound, to its own thickness., , b), , The internal width of each added plate, between the lines of welds or fasteners, connecting it to the original section to its own, thickness., , c), , element (b,), , are capable of effectively transmitting all the horizontal, forces directly to the foundations, the structural steel, framework may be designed without considering the, effect of wind or earthquake., 3.9.3 Wind and earthquake forces are reversible and, therefore call for rigidity and strength under force, reversal in both longitudinal and transverse directions., To resist torsional effects of wind and earthquake, forces, bracings in plan should be provided and, integrally, connected, with the longitudinal, and, transverse bracings, to impart adequate torsional, resistance to the structure., , Any outstand of the added plates beyond the, line of welds or fasteners connecting it to, original section to its own thickness., , 3.8 Maximum, , Effective, , Slenderness, , Ratio, , The maximum effective slenderness ratio, KZlr values, of a beam, strut or tension member shall not exceed, those given in Table 3. ‘KL’ is the effective length of, the member and ‘r‘ is appropriate radius of gyration, based on the effective section as defined in 3.6.1., , 3.9.3.1 In shed type steel mill buildings, adequate, bracings shall be provided to transfer the wind or, earthquake loads from their points of action to the, appropriate, supporting, members., Where the, connections, to the interior columns or frames are, designed such that the wind or earthquake loads will, not be transferred, to the interior, columns,, the, exterior columns or frames shall be designed to resist, the total wind or earthquake, loads., Where the, connections to the interior columns and frames are, designed such that the wind or earthquake effects, are transferred, to the interior columns also, and, where adequate, rigid diaphragm, action can be, mobilized as in the case of the cast-in place RC slab,, both exterior and interior columns and frames may, be designed on the assumption, that the wind or, earthquake load is divided among them in proportion, to their relative stiffness., Columns also should be, designed to withstand the net uplifting effect caused, by excessive wind or earthquake., Additional axial, forces arising in adjacent columns due to the vertical, component of bracings or due to frame action shall, also be accounted for., , Table 3 Maximum Values of Effective, Slenderness Ratios, s}, No., , Member, , Maximum, Effective, Slenderness, Ratio, , (1), , (2), , (3), , A member carrying compressive loads, resulting from dead loads and imposed, loads, A tension member in which a reversal, of direct stress occurs due to loads other, than wind or seismic forces, , 180, , (KU-), , i), ii), , iii), , A member subjected to compression, , 180, , 250, , forces resulting only from combination, with wind/earthquake actions, provided, the deformation of such member does, not adversely affect tbe stress in any, part of the structure, iv), , Compression flange of a beam against, lateral torsional buckling, , 300, , v), , A member normally acting m a tie in a, roof truss or a bracing system not, considered effective when subject to, possible reversal of stress into, compression resulting from the action, of wind or earthquake forces]], , 350, , 3.9.3.2 Earthquake, forces are proportional, to the, seismic mass as defined in IS 1893. Earthquake forces, should be applied at the centre of gravity of all such, components of mass and their transfer to the foundation, should be ensured., Other construction, details,, stipulated in IS 4326 should also be followed., , Members always under tension’) (other, 400, than pre-tensioned members), I) Tension, members,, such as bracing’s, pre-tensioned to avoid, sag, need not satisfy tbe maximum slenderness ratio limits., vi), , 3.9 Resistance, , to Horizontal, , 3.9.3.3 In buildings where high-speed traveling cranes, are supported or where a building or structure is, otherwise subjected to vibration or sway, triangulated, bracing or rigid portal systems shall be provided to, reduce the vibration, or sway to an acceptable, minimum., , Forces, , 3.9.1 In designing the steel frame work of a building,, provision, shall be made (by adequate, moment, connections or by a system of bracing) to effectively, transmit to the foundations all the horizontal forces,, giving due allowance for the stiffening effect of the, walls and floors, where applicable., , 3.9.4 Foundations, The foundations of a building or other structures shall, be designed to provide the rigidity and strength that, has been assumed in the analysis and design of the, superstructure., , 3.9.2 When the walls, or walls and floors and/or roofs, 20

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IS 800:2007, 3.9.5 Eccentrically Placed Loads, , at the centre of the building or building section, the, length of the building section may be restricted to, 180 m in case of covered buildings and 120 m in case, of open gantries (see Fig. 3)., , Where a wall, or other gravity load, is placed, eccentrically upon the flange of a supporting steel, beam, the beam and its connections shall be designed, for torsion, unless the beam is restrained laterally in, such a way as to prevent the twisting of the beam., 3.10 Expansion, 3.10.1 In view of, in deciding the, expansion joints,, expansion joints, designer., , Joints, the large number of factors involved, location,, spacing and nature of, the decision regarding provision of, shall be left to the discretion of the, , L--.-——,,om~, , 3.10.2 Structures in which marked changes in plan, dimensions take place abruptly, shall be provided with, expansion joints at the section where such changes, occur. Expansion joints shall be so provided that the, necessary movement occurs with minimum resistance, at the joint. The gap at the expansion joint should be, such that:, a), , It accommodates, the expected expansion, contraction, due to seasonal and durinal, variation of temperature, and, , b), , It avoids pounding of adjacent units under, earthquake. The structure adjacent to the joint, should preferably be supported on separate, columns but not necessarily, on separate, foundations., , END OF COVERED BUILDING/SECTION, FIG. 3 MAXIMUMLENGTHOF BUILDINGWITHONE, BAY OF BRACING, 3.10.3.2 If more than one bay of longitudinal bracing, is provided near the centre of the buildinglsection, the, maximum centre line distance between the two lines, of bracing may be restricted to 50 m for covered, buildings, (and 30 m for open gantries), and the, maximum distance between the centre of the bracing, to the nearest expansion jointiend of building or section, may be restricted to 90 m (60 m in case of open, gantries). The maximum length of the building section, thus may be restricted to 230 m for covered buildings, (150 m for open gantries)., Beyond this, suitable, expansion joints shall be provided (see Fig. 4)., , 3.10.3 The details as to the length of a structure where, expansion, jdints have to be provided, may be, determined after taking into consideration, various, factors such as temperature, exposure to weather and, structural design. The provisions in 3.10.3.1 to 3.10.3.3, are given as general guidance., 3.10.3.1 If one bay of longitudinal, , 3.10.3.3 The maximum width of the covered building, section should preferably be restricted to 150 m beyond, which suitable provisions for the expansion joint may, be made., 3.10.4 When the provisions of these sections are met, for a building or open structure, the stress analysis due, to temperature is not required., , bracing is provided, , +, , EXPANSION, JOINT, , i, , i, i, :, —90m, , —50m~, , 90 m, , “, , i, ‘D, i, I, , FIG. 4 MAXIMUMLENGTHOF BUILDING/SECTIONWITHTwo BAYSOF BRACINGS, , 21

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IS 800:2007, , METHODS, , SECTiON 4, OF STRUCTURAL, , loading given in 4.3.6 satisfies the following, criteria:, , ANALYSIS, , 1), 4.1 Methods, , of Determining, , Action Effects, , 4.1.1 General, For the purpose of complying with the requirements, of the limit states of stability, strength and serviceability, specified in Section 5, effects of design actions on a, structure and its members and connections, shall be, determined by structural analysis using the assumptions, of 4.2 and 4.3 and one of the following methods of, analysis:, a), , Elastic analysis in accordance, , with 4.4,, , b), , Plastic analysis in accordance, , with 4.5,, , c), , Advanced, analysis, Annex B, and, , d), , Dynamic analysis in accordance, (Part 1)., , in accordance, , 65A, 2, 2), , credible, , earthquake, , 3), , with, , with IS 1893, , Assumed, , for Structural, , 4.2.1 The effects of design action in the members and, connections of a structure shall be determined by, assuming singly or in combination of the following, forms of construction (see 10.6.1)., 4.2.1.1 Rigid construction, In rigid construction,, the connections, between, members (beam and column) at their junction shall be, assumed to have sufficient rigidity to hold the original, angles between the members connected at a joint, unchanged under loading., , For the purpose of analysis and design, the structural, frames are classified as non-sway and sway frames as, given below:, , c), , A frame,, which, when, analyzed, considering, all the lateral supporting, system does not comply with the above, criteria, should be classified as a sway, frame. even if it is braced or otherwise, laterally stiffened., , 4.2 Forms of Construction, Analysis, , loads shall be assumed, , 4.1.2 Non-sway and Sway Frames, , b), , For unclad frame or clad frames, when, the stiffening effect of the cladding is, taken into account in the deflection, calculations:, , 4000, , to the load at which significant plastic, to correspond, hinges, are formed, in the structure, and the, corresponding effects shall be obtained by plastic or, advanced analysis. More information on analysis and, design to resist earthquake is given in Section 12 and, IS 1893 (Part 1)., , a), , 000, , 65A, , The design action effects for design basis earthquake, loads shall be obtained only by an elastic analysis. The, maximum, , For clad frames, when the stiffening, effect of the cladding is not taken into, account in the deflection calculations:, , Non-sway, , frame — One in which the, transverse displacement, of one end of the, member relative to the other end is effectively, prevented. This applies to triangulated frames, and trusses or to frames where in-plane, stiffness is provided by bracings, or by shear, walls, or by floor slabs and roof decks secured, horizontally to walls or to bracing systems, parallel to the plane of loading and bending, of the frame., , 4.2S.2 Semi-rigid construction, In semi-rigid construction, the connections between, members (beam and column) at their junction may not, have sufficient rigidity to hold the original angles, between the members at a joint unchanged, but shall, be assumed to have the capacity to furnish a dependable, and known degree of flexural restraint. The relationship, between the degree of flexural restraint and the level, of the load effects shall be established by any rational, method or based on test results (see Annex F)., , Sway frame — One in which the transverse, displacement, of one end of the member, relative to the other end is not effectively, prevented. Such members and frames occur, in structures which depend on flexural action, of members to resist lateral loads and sway,, as in moment resisting frames., , 4.2.1.3 Simple construction, In simple construction,, the connections, between, members (beam and column) at their junction will not, resist any appreciable moment and shall be assumed, to be hinged., , A rigid jointed multi-storey frame may be, considered as a non-sway frame if in every, individual storey, the deflection 6, over a, storey height h,, due to the notional horizontal, , 4.2.2 Design of Connections, The design of all connections, , 22, , shall be consistent with

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IS 800:2007, the form of construction,, , and the behaviour, , c), , of the, , connections, shall not adversely affect any other part, of the structure beyond what is allowed for in design., , Connections, Section 10., , shall be designed, , 4.3 Assumptions, , in accordance, , with, , in Analysis, , 4.3.1 The structure, except as follows:, , shall be analyzed, , in its entirety, , Where the imposed load is variable and, exceeds three-quarters, of the dead load,, arrangements of live load acting on the floor, under consideration, shall include, the, following cases:, 1), , Imposed load on alternate spans,, , 2), , Imposed load on two adjacent spans, and, , - 3), , Imposed load on all the spans., , 4.3.4 Base Sti@ess, a), , b), , c), , Regular building structures, with orthogonal, frames in plan, may be analyzed as a series, of parallel two-dimensional, sub-structures, (part of a structure), the analysis being carried, out in each of the two directions, at right, angles to each other, except when there is, significant load redistribution, between the, sub-structures, (part of a structure)., For, earthquake loading three dimensional analysis, may be necessary to account for effects of, torsion, and also for multi-component, earthquake forces [see IS 1893 (Part 1)]., , In the analysis of all structures the appropriate base, stiffness about the axis under consideration shall be, used. In the absence of the knowledge of the pedestal, and foundation, stiffness,, the following, may be, assumed:, , For vertical loading in a multi-storey building, structure, provided with bracing or shear walls, to resist all lateral forces, each level thereof,, together with the columns immediately above, and below, may be considered, as a substructure, the columns being assumed fixed, at the ends remote from the level under, consideration., Where beams at a floor level in a multi-bay, building structure tu-e considered as a substructure (part of a structure), the bending, moment at the support of the beam due to, gravity loads may be determined based on the, assumption that the beam is fixed at the i%, end support, one span away from the span, under consideration, provided that the floor, beam is continuous beyond that support point., , 4.3.2 Spun Length, , a), , When the column is rigidly connected to a, suitable foundation,, the stiffness of the, pedestal shall be taken as the stiffness of the, column above base plate. However in case of, very stiff pedestals, and foundations, the, column may be assumed as fixed at base., , b), , When the column is nominally connected, to the foundation,, a pedestal stiffness of, 10 percent of the column stiffness may be, assumed., , c), , When an actual pin or rocker is provided in, the connection between the steel column and, pedestal, the column is assumed as hinged at, base and the pedesrdl and foundation maybe, appropriately designed for the reactions from, the column., , d), , In case of (a) and (b), the bottom of the, pedestal, shall be assumed, to have the, following boundary condition in the absence, of any derailed procedure based on theory or, tests:, 1), , When the foundation consist of a group, of piles with a pile cap, raft foundation, or an isolated footing resting on rock or, very hard soil, the pedestal shall be, assumed to be fixed at the level of the, bottom of footing or at the top of pile, cap., , 2), , When the foundation, consist of an, isolated footing resting on other soils,, pedestal shall be assumed to be hinged, at the level of the bottom of footing., , 3), , When the pedestal is supported by a, single pile, which is laterally surrounded, by soil providing passive resistance, the, pile shall be assumed to be fixed at a, depth of 5 times the diameter of the pile, , The span length of a flexural member iu a continuous, frame system shall be taken as the dlsiance between, centre-to-centre of the supports., 4.3.3 Arrangements of Imposed Loads in Bui[ding.s, For building structures, the various arrangements of, imposed loads considered for the analysis, shall include, at least the following:, a), b), , Where the loading pattern, arrangement concerned., , is fixed,, , the, , Where the imposed load is variable and not, greater than three-quarters of the dead load,, the live load may be taken to be acting on all, spans., 23

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IS 800:2007, 4.4.2 First-Order Elastic Analysis, , below the ground level in case of compact, ground or the top level of compact soil, in case of poor soil overlying compact, soil., , Bending members may be assumed to have their ends, connected for shear only and to be free to rotate. In, triangulated structures, axial [orces maybe determined, by assuming that all members are pin connected. The, eccentricity for stanchion and column shall be assumed, in accordance with 7.3.3., , In a first-order elastic analysis, the equilibrium of the, frame in the undeformed geometry is considered, the, changes in the geometry of the frame due to the loading, are not accounted for, and changes in the effective, stiffness of the members, due to axial force are, neglected. The effects of these on the first-order, bending moments shall be allowed for by using one of, the methods of moment amplification, of 4.4.3.2, or 4.4.3.3, as appropriate., Where the moment, amplification factor CY, CZ, calculated in accordance, with 4.4.3.2 or 4.4.3.3 as appropriate, is greater than, 1.4, a second-order elastic analysis in accordance with, Annex B shall be carried out., , 4.3.6 Notional Horizontal, , 4.4.3 Second-Order Elastic Analysis, , 4), , When the column is founded into rock,, it may be assumed to be fixed at the, interface of the column and rock., , 4.3.5 Simple Construction, , Loads, , 4.4.3.1 The analysis shall allow for the effects of the, , To analyze a frame subjected, to gravity loads,, considering the sway stability of the frame, notional, horizontal forces should be applied. These notional, horizontal forces account for practical imperfections, and should be taken at each level as being equal to 0.5, percent of factored dead load plus vertical imposed, loads applied at that level. The notional load should, not be applied along with other lateral loads such as, wind and earthquake loads in the analysis., 4.3.6.1 The notional forces should be applied, whole structure, in both orthogonal directions,, direction at a time, at roof and all floor levels, equivalent,, They should, be taken as, simultaneously with factored gravity loads., -----. ., .., ., 4.3.6 ..4 1he nohonal force should nOt be,, a), , applied when considering, overall instability;, , b), , combined, loads;, , c), , combined, , d), , taken to contribute, foundation., , with other, , with temperature, , on the, in one, or their, acting, , overturning, , horizontal, , design loads acting on the structure and its members, in their displaced and deformed configuration. These, second-order effects shall be taken into account by, using eithe~, a), , A first-order elastic analysis with moment, amplification, in accordance, with 4.4.2,, provided the moment amplification factors,, C, and C, are not greater than 1.4; or, , b), , A second-order elastic analysis in accordance, with Annex B., , 4.4.3.2 Moment amplification for members in non-sway, , frames, For a member with zero axial compression or a member, subject to axial tension, the design bending moment is, that obtained from the first order analysis for factored, loads, without any amplification., , or, , (lateral), , For a braced member with a design axial compressive, force P~ as determined by the first order analysis, the, design bending moment shall be calculated considering, moment amplification as in 9.3.2.2., , effects; and, , to the net shear on the, , 4.4.3.3 Moment amplification for members in sway, , 4.3.6.3 The sway effect using notional load under, gantry load case need not be considered if the ratio of, height to lateral width of the building is less than unity., , frames, The design bending moment shall be calculated as the, product of moment amplification factor [see 9.3.2.2, (C~Y, Cm,)] and the moment obtained from the first, order analysis of the sway frame, unless analysis, considering, second order effects is carried out, (see 4.4.3)., , 4,4 Elastic Analysis, 4.4.1 Assumptions, Individual members shall be assumed to remain elastic, under the action of the factored design loads for all, limit states., , 4.4.3.4 The calculated bending moments from the first, order elastic analysis may be modified by redistribution, upto 15 percent of the peak calculated moment of the, member under factored load, provided that:, , The effect of haunching or any variation of the crosssection along the axis of a member shall be considered,, and where significant, shall be taken into account in, the determination of the member stiffness,, , a), , 24, , the internal, , forces, , and moments, , in the

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IS 800:2007, members of the frame are in equilibrium, applied loads., b), , fluctuating, assessment, , with, , all the members in which the moments are, reduced shall belong to plastic or compact, section classification (see 3.7)., , If practicable,, torsional restraint (against lateral, buckling) should be provided at all plastic hinge, locations. Where not feasible, the restraint should be, provided within a distance of D/2 of the plastic hinge, location, where D is the total depth of section., , 4.5.1 Application, The effects of design action throughout or on part of a, structure may be determined by a plastic analysis,, provided that the requirements of 4.5.2 are met. The, distribution, of design action effects shall satisfy, equilibrium and the boundary conditions., , The torsional restraint requirement, at a section as, above, need not be met at the last plastic hinge to form,, provided it can be clearly identified., Within a member containing, a plastic hinge, the, maximum distance L~ from the restraint at the plastic, hinge to an adjacent restraint should be calculated by, any rational method or the conservative method given, below, so as to prevent lateral buckling., , 4.5.2 Requirements, When a plastic method of analysis is used, all of the, following conditions shall be satisfied, unless adequate, ductility of the structure and plastic rotation capacity, of its members and connections are established for the, design loading conditions by other means of evaluation:, The yield stress of the grade of the steel used, shall not exceed 450 MPa., , b), , The stress-strain characteristics of the steel, shall not be significantly different from those, obtained for steels complying with IS 2062, or equivalent and shall be such as to ensure, complete plastic moment redistribution. The, stress-strain diagram shall have a plateau at, the yield stress, extending for at least six times, the yield strain. The ratio of the tensile, strength to the yield stress specified for the, grade of the steel shall not be less than 1.2., The elongation on a gauge length complying, with IS 2062 shall not be than 15 percent, and, the steel shall exhibit strain-hardening, capability. Steels conforming to IS 2062 shall, be deemed to satisfy the above requirements., , c), , The members used shall be hot-rolled or, fabricated using hot-rolled plates and sections., , d), , The cross-section of members not containing, plastic hinges should be at least that of, compact section (see 3.7.2), unless the, members meet the strength requirements from, elastic analysis., , e), , Where plastic hinges occur in a member, the, proportions of its cross-section, should not, exceed the limiting values for plastic section, given in 3.7.2., , f), , The cross-section, should, about its axis perpendicular, plastic hinge rotation., , $4, , a fatigue, , 4.5.2.1 Restraints, , 4.5 Plastic Analysis, , a), , loading,, requiring, (see Section 13)., , Conservatively, , L~ (ht mm) may be taken as, , where, actual compressive, stress on the crosssection due to axial load, in N/mm*;, , f=, f,, , = yield stress, in N/mm2;, , ‘Y, , =, , radius of gyration about the minor axis, in, mm;, , Xt, , =, , torsional index, x, =1.132 (Alw/IylJ0”5;, , A=, , area of cross-section;, , and, , Iw, Iy, It = warping constant, second moment of the, cross section above the minor axes and, St. Venant’s torsion constant, respectively., Where the member has unequal flanges, rY should be, taken as the lesser of the values of the compression, flange only or the whole section., Where the cross-section of the member varies within, the length L~, the maximum value of rY and the, minimum value of xl should be used., The spacing of restraints, to member lengths not, containing, a plastic, hinge should, satisfy, the, recommendations, of section on lateral buckling, strength of beams (see 8.2.2). Where the restraints are, placed at the limiting distance L~, no further checks, are required., , be symmetrical, to the axis of the, , 4.5.2.2 Stiffeners at plastic hinge locations, Web stiffeners should be provided where a concentrated, load, which exceeds 10 percent of the shear capacity, , The members shall not be subject to impact, loading, requiring fracture assessment, or, , 25

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IS 800:2007, of the member, is applied within D\2 of a plastic hinge, location (see 8.2.1.2). The stiffener should be provided, within a distance of half the depth of the member on, either side of the hinge location and be designed to, carry the applied load in accordance with 8.7.4. If the, stiffeners are flat plates, the outstand width to the, thickness ratio, b/t, should not exceed the values given, in the plastic section (see 3.7, Table 2). Where other, , I, sections are used the ratio, , ~, [)It, , In the case of building structures, it is not normally, necessary to consider the effect of alternating plasticity., 4.5.4 Second-Order Elastic Analysis, Any second-order effects of the loads acting on the, structure, in its deformed, configuration, may be, neglected, provided the following are satisfied:, a), , m, should not exceed, , the values given for plastic section (for simple outstand,, as in 3.7);, where, , Iso = second moment of area of the stiffener about, ‘the face of the element perpendicular, web; and, I,, , to the, , = St. Venant’s torsion constant of the stiffener., b), , 4.5.2.3 The frame shall be adequately supported against, sway and out-of-plane buckling, by bracings, moment, resisting frame or an independent system such as shear, wall., , 4.5.2.4 Fabrication, , restriction, , Within a length equal to the member depth, on either, side of a plastic hinge location,, the following, restrictions should be applied to the tension flange and, noted in the design drawings. Holes if required, should, be drilled or else punched 2 mm undersize and reamed., All sheared or hand flame cut edges should be finished, smooth by grinding, chipping or planning., , 4.6 Frame, , 4.5.3 Assumptions in Analysis, The design action effects shall be determined, rigid-plastic analysis., , b), , c), , Buckling, , Analysis, , 4.6.1 The elastic buckling load factor ().C,) shall be the, ratio of the elastic buckling load set of the frame to the, design load set for the frame, and shall be determined, in accordance with 4.6.2., NOTE— The value of lC, depends on the load set and has to, , using a, , It shall be permissible to assume full strength or partial, strength connections, provided the capacities of these, are used in the analysis, and provided that, a), , For clad frames, provided the stiffening effects, of masonry infill wall panels or diaphragms of, profiled wall panel is not taken into account,, and where elastic buckling load factor, JC,, (see 4.6) satisfies J,jAP> 10., [f10>2C{IP24,6 the second-order effects may, be considered by ampli~ing the design load, effects obtained from plastic analysis by a, factor 6,= {0.9 2,, /( 2=,- l)}., If ACj JP < 4.6, second-order, elasto-plastic, analysis or second-order, elastic analysis, (see 4.4.3) is to be carried out., For un-clad frames or for clad frames where, the stiffening effects of masonry infill or diaphragms of profiled wall panel is taken into, account, where elastic buckling load factor, 2<,, (see 4.6) satisfies J=j 2,220, If 20> AC]AP, 25.75 the second-order effects, may be considered by ampli~ing the design, load effects obtained from plastic analysis by, a factor iSP= {0.9 2,,/( J,,–I)}., If IC{ LP<5.75, second-order elasto-plastic, analysis or second-order, elastic analysis, (see 4.4.3) shall be carried out., , be evaluated for each possible set of load combination., , 4.6.2 In-plane Frame Buckling, The elastic buckling load factor (hC,) of a rigid-jointed, frame shall be determined by using:, , in a full strength connection, the moment, capacity of the connection shall be not less, than that of the member being connected;, in a partial strength connection, the moment, capacity of the connection may be less than, that of the member being connected; and, in both cases the behaviour of the connection, shall be such as to allow all plastic hinges, necessary for the collapse mechanism, to, develop, and shall be such that the required, plastic hinge rotation does not exceed the, rotation capacity at any of the plastic hinges, in the collapse mechanism., , a), , One of the approximate, and 4.6.2.2 or, , methods, , b), , A rational elastic buckling, whole frame., , of 4.6.2.1, , analysis, , of the, , 4.6.2.1 Regular non-sway frames (see 4.1.2), In a rectangular non-sway frame with regular loading, and negligible axial forces in the beams, the Euler, buckling stressfCC,for each column shall be determined, in accordance with 7.1.2.1. The elastic buckling load, factor (L,,) for the whole frame shall be taken as the, lowest of the ratio of (&/fed) for all the columns, where, 26

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IS 800:2007, fC~is the axial compressive, the factored load analysis., , disproportionately, under accidental events, like explosions,, vehicle impact or due to, consequences, of human error to an extent, beyond local damage. The potential, for, catastrophic, damage shall be limited or, avoided by appropriate choice of one or more, of the following:, , stress in the column from, , 4.6.2.2 Regular sway frames, In a rectangular sway frame with regular loading and, negligible axial forces in the beams, the buckling load,, PC,,,for each column shall be determined as P,, = A~C, wherefCCis the elastic buckling stress of the column in, the plane of frame, obtained in accordance with 7.1.2.1., The elastic buckling load factor AC,,for the whole frame, shall be taken as the lowest of all the ratios, k,,,,, calculated for each storey of the building, as given, below:, , 1), , Avoiding,, eliminating, or reducing, exposure to hazards, which the structure, is likely to sustain., , 2), , Choosing structural forms, layouts and, details and designing such that:, , ‘c’ -, , ~(P/L), , where, P=, , L=, , i), , the structure has low sensitivity, hazardous conditions; and, , ii), , the structure survives with only local, damage even after serious damage, to any one individual element by the, hazard., , _ ~(PCC/L), , ~, , member axial force from the factored load, analysis, with tension taken as negative; and, , 3), , column length and the summation includes, all columns in the plane frame within a, storey., SECTION 5, LIMIT STATE DESIGN, , Choosing suitable material, design and, detailing, procedure,, construction, specifications, and control procedures for, shop fabrication and field construction as, relevant to the particular structure., , The following conditions may be satisfied to avoid a, disproportionate collapse:, a), , 5.1 Basis for Design, 5.1.1 In the limit state design method, the structure, shall be designed to withstand safely all loads likely to, act on it throughout its life. It shall not suffer total, collapse under accidental loads such as from explosions, or impact or due to consequences of human error to an, extent beyond the local damages. The objective of the, design is to achieve a structure that will remain fit for, use during its life with acceptable target reliability. In, other words, the probability of a limit state being, reached during its lifetime should be very low. The, acceptable limit for the safety and serviceability, requirements before failure occurs is called a limit state., In general, the structure shall be designed on the basis, of the most critical limit state and shall be checked for, other limit states., 5.L2 Steel structures are to be designed and constructed, to satisfy the design requirements, with regard to, stability, strength, serviceability,, brittle fracture,, fatigue, fire, and durability such that they meet the, following:, a), , Remain fit with adequate reliability and be, able to sustain all actions (loads) and other, influences experienced during construction, and use;, , b), , Have adequate, maintenance;, , c), , Do not suffer overall, , durability, , to, , under, , damage, , normal, , or collapse, 27, , The building, should be effectively, tied, together at each principal floor level and each, column should be effectively held in position, by means of continuous ties (beams) nearly, orthogonal,, except where the steel work, supports only cladding weighing not more, than 0.7 kN/m~ along with imposed and wind, loads. These ties must be steel members such, as beams, which may be designed for other, purposes, steel bar reinforcement anchoring, the steel frame to concrete floor or steel mesh, reinforcement, in composite slab with steel, profiled sheeting directly connected to beam, with shear connectors. These steel ties and, their end connections should be capable of, resisting factored tensile force not less than, the factored dead and imposed loads acting, on the floor area tributary to the tie nor less, than 75 kN. Such connection of ties to edge, column should also be capable of resisting, 1 percent of the maximum axial compression, in the column at the level due to factored dead, and imposed loads. All column splices should, be capable of resisting a tensile force equal, to the largest of a factored dead and live load, reaction from a single floor level located, between that column splice and the next, column splice below that splice. Lateral load, system to resist notional horizontal loads, prescribed, in 4.3.6 should be distributed

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IS 800:2007, no longer satisfies the performance, requirements, specified. The limit states are classified as:, , throughout the building in nearly orthogonal, directions so that no substantial portions is, connected at only one point to such a system., Precast concrete or other heavy floor or roof, units should be effectively anchored in the, direction of their span either to each other over, the support or directly to the support., b), , c), , a), , Limit state of strength; and, , b), , Limit state of serviceability., , a), , Loss of equilibrium of the structure as a whole, or any of its parts or components., , b), , Loss of stability of the structure (including, the effect of sway where appropriate, and, overturning), or any of its parts including, supports and foundations., , c), , Failure by excessive deformation, rupture of, the structure or any of its parts or components,, , d), , Fracture due to fatigue,, , e), , Brittle fracture., , t, 5.2.2.1 The limit states of strength are those associated, with failures (or imminent failure), under the action of, probable and most unfavorable, combination of loads, on the structure using the appropriate partial safety, factors, which may endanger the safety of life and, property. The limit state of strength includes:, , Where the above conditions to tie the columns, to the floor adequately are not satisfied each, storey of the building should be checked to, ensure that disproportionate, collapse would, not precipitate by the notional removal, one, at a time, of each column., Where each floor is not laterally supported, by more than one system, check should be, made at each storey by removing one such, lateral support system at a time to ensure that, disproportionate, collapse would not occur., The collapse is considered disproportionate,, if more than 15 percent of the floor or roof, area of 70 mz collapse at that level and at one, adjoining level either above or below it, under, a load equal to 1.05 or 0.9 times the dead load,, 0.33 times temporary or full imposed load of, permanent nature (as in storage buildings) and, 0.33 times wind load acting together., , 5.2.2.2 The limit state of serviceability, , 5.1.3 Structures, designed for unusual or special, functions, shall comply with any other relevant, additional limit state considered appropriate to that, structure., , a), , Deformation, and deflections,, which may, adversely affect the appearance or effective, use of the structure or may cause improper, functioning of equipment or services or may, cause damages to finishes and non-structural, members., , b), , Vibrations, in the structure, or any of its, components causing discomfort to people,, damages to the structure, its contents or which, may limit its functional effectiveness. Special, consideration, shall be given to systems, susceptible to vibration, such as large open, floor areas free of partitions to ensure that, such vibrations are acceptable for the intended, use and occupancy (see Annex C)., , c), , Repairable, , damage or crack due to fatigue., , d), , Corrosion,, , durability., , e), , Fire., , 5.1.4 Generally, structures, and elements shall be, designed by limit state method. Where limit state, method cannot be conveniently adopted, working stress, design (see Section 11) may be used., 5.2 Limit State Design, 5.2.1 For achieving the design objectives, the design, shall be based on characteristic, values for material, strengths and applied loads (actions), which take into, account the probability of variations in the material, strengths and in the loads to be supported., The, characteristic values shall be based on statistical data,, if available. Where such data is not available, these, shall be based on experience. The design values are, derived from the characteristic values through the use, of partial safety factors, both for material strengths and, for loads. In the absence of special considerations, these, factors shall have the values given in this section, according to the material, the type of load and the limit, state being considered. The reliability of design is, ensured by satisfying the requirement:, , include:, , 5.3 Actions, The actions (loads) to be considered in design include, direct actions (loads) experienced by the structure due, to self weight, external actions etc., and imposed, deformations, such as that due to temperature and, settlements., 5.3.1 Classification ofActions, Actions are classified, given below:, , by their variation, , with time as, , Design action S Design strength, a), 5.2.2 Limit states are the states beyond which the structure, , Permanent actions (Q ): Actions due to selfweight, , 28, , of structura, , ! and non-structural

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. ._,. ___, , —, , LS 800:2007, components, fittings,, equipment, etc., b), , c), , ancillaries,, , is generally not required in building unless it is required, by client or approving, authority, in which case,, generally recommendation, in 5.1.2 c) or specialist, literature shall be followed., , and fixed, , Variable actions (Qv): Actions, due to, construction and service stage loads such as, imposed (live) loads (crane loads, snow loads,, etc.), wind loads, and earthquake loads, etc., , 5.3.3 Design Actions, , The Design Actions, Q~,is expressed as Qd = ~?’., , Accidental actions (Q,): Actions expected due, to explosions,, , and impact of vehicles, etc., where, , 5.3.2 Characteristic Actions (Loads), , yk, , 5.3.2.1 The Characteristic, , Actions, QC,are the values, of the different actions that are not expected to be, exceeded with more than 5 percent probability, during, the life of the structure and they are taken as:, a), , the variable loads, values of which are, specified in relevant standard [see IS 875 (all, Parts) and IS 1893 (Part l)]., , c), , the upper limit with a specified probability, (usually 5 percent) not exceeding during some, reference period (design life)., , a), , Possibility of unfavorable, deviation of, the load from the characteristic value,, , b), , Possibility, the load,, , c), , Uncertainty in the assessment of effects, of the load, and, , d), , Uncertainty in the assessment, limit states being considered., , of the, , The loads or load effects shall be multiplied, , by the, , assessment, , of, , 5.4 Strength, The ultimate, strength, calculation, consideration of the following:, , 5.3.2.2 The characteristic values of accidental loads, generally correspond to the value specified by relevant, code, standard or client. The design for accidental load, Safety Factors, , of inaccurate, , relevant ~f factors, given in Table 4, to get the design, loads or design load effects., , specified, by client,, or by designer, in, consultation with client, provided they satisfy, the minimum provisions, of the relevant, loading standard., , Table 4 Partial, , loads k,, , = partial safety factor for different, given in Table 4 to account for:, , the self-weight, in most cases calculated on, the basis of nominal dimensions, and unit, weights [see 1S 875 (Part 1)]., , b), , d), , Q,k, , k, , may require, , a), , Loss of equilibrium, part of it, considered, , of the structure or any, as a rigid body; and, , b), , Failure by excessive deformation,, , rupture or, , for Loads, y~,for Limit States, , (Clauses 3.5.1 and 5.3.3), Limit State of Strength, , Combination, , Limit State of Serviceability, , F, “, (1), DL+LL+CL, DL+LL+CL+, WLJEL, DL+WLfEL, DL+ER, DL+LL+AL, , (2), 1.5, 1.2, 1’.2, 1.5(0.9)2’, ~~;)z), 1.0, , ~, Leading, , ‘“L, , Y, , T, , “, , “, , 7, &, , ‘m’, , Accompanying, , Accompanying, , (3), , (4), , (5), , 1.5, 1.2, 1.2, —, 1.2, , 1.05, 1.05, 0.53, —, —, , —, 0.6, 1.2, 1.5, —, , 0.35, , 0.35, , —, , (7), , (8), , (9), , (lo), , —, —, , 1.0, 1.0, , 1.0, 0.8, , 1.0, 0.8, , —, 0.8, , —, ——, , 1.0, , —, —, , —, —, , 1.0, —, , 1.0, , —, , —, , (6), , —, , —, , ‘)When action of different live loads is simultaneously considered, the leading live load shall be considered to be the one causing the, higher load effects in the member/section., ‘)This value is to be considered when the dead load contributes to stability against overturning is critical or the dead load causes, reduction in stress due to other loads., , Abbreviations:, DL = Dead load, LL = Imposed load (Live loads), WL = Wind load, CL = Crane load (VerticaVHorizontal), AL = Accidental load, ER =, Erection load, EL= Earthquake load., NOTE — The effects of actions (loads) in terms of stresses or stress resultants may be obtained from an appropriate method of analysis, m in 4., , 29

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IS 800:2007, loss of stability of the structure or any part of, it including support and foundation., , c), , The permanent actions (loads) and effects, contributing to resistance shall be multiplied, with a partial safety factor 0.9 and added, together, with design, resistance, (after, multiplying with appropriate partial safety, factor). Variable actions and their effects, contributing to resistance shall be disregarded., , d), , The resistance effect shall be greater than or, equal to the destabilizing effect. Combination, of imposed and dead loads should be such as, to cause most severe effect on overall stability., , 5.4.1 Design Strength, The Design Strength, S~, is obtained as given below, from ultimate strength, SUand partial safety factors for, materials, y~ given in Table 5., , Sd=s,lym, where partial safety factor for materials, y~ account, for:, of unfavorable, deviation of, a) Possibility, material strength from the characteristic value,, b), , Possibility, of unfavorable, member sizes,, , c), , Possibility, of unfavorable, reduction, in, member strength due to fabrication, and, tolerances, and, , d), , Uncertainty in the calculation, the members., , 5.5 Factors, , Governing, , the Ultimate, , variation, , 5.5.1.2 Sway stability, The whole structure, including portions between, expansion joints, shall be adequately stiff against sway., To ensure this, in addition to designing for applied, horizontal loads, a separate check should be carried, out for notional horizontal loads such as given in 4.3.6, to evaluate the sway under gravity loads., , of, , of strength of, , 5.5.2 Fatigue, Generally fatigue need not be considered unless a, structure, or element, is subjected, to numerous, significant fluctuations of stress. Stress changes due, to fluctuations in wind loading normally need not be, considered. Fatigue design shall be in accordance with, Section 13. When designing for fatigue, the partial, safety factor for load, yf, equal to unity shall be used, for the load causing stress fluctuation and stress range., , Strength, , Stability, , 5.5.1, , Stability shall be ensured for the structure as a whole, and for each of its elements. This should include,, overall frame stability against overturning and sway,, as given in 5.5.1.1 and 5.5.1.2., 5.5.1.1 Stability against overturning, , 5.5.3 Plastic Collapse, , The structure as a whole or any part of it shall be, designed to prevent instability due to overturning, uplift, or sliding under factored load as given below:, a), , b), , Plastic analysis and design may be used, if the, requirement, specified under the plastic method of, analysis (see 4.5) are satisfied., , The Actions shall be divided into components, aiding instability and components resisting, instability., , 5.6 Limit State of Serviceability, Serviceability, limit state is related to the criteria, governing normal use. Serviceability limit state is limit, state beyond which the service criteria specified below,, are no longer met:, , The permanent and variable actions and their, effects causing instability shall be combined, using appropriate load factors as per the Limit, State requirements,, to obtain maximum, destabilizing effect., Table 5 Partial, , a), , Safety Factor, , Deflection, , for Materials,, , limit,, y~, , (Clause 5.4. 1), SI, , Definition, , Partial Safety Factor, , No., , i), ii), iii), iv), , 1.10, , Resistance, governed by yielding, Ymo, Resistance of member to buckling, ymo, Resistance, governed by ultimate stress, y~t, Resistance of connection:, a), b), c), d), , 1.10, 1.25, , Bolts-Friction Type, y~r, Bolts-Bearing Type, ym~, Rivets, Ym,, Welds, ymW, , 30, , Shop Fabrications, , Field Fabrications, , 1.25, 1.25, 1.25, 1.25, , 1.25, 1.25, 1.25, 1.50

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IS 800:2007, b), , Vibration limit,, , c), , Durability consideration,, , d), , Fire resistance., , or a building component should not impair the strength, of the structure or components or cause damage to, finishings. Deflections are to be checked for the most, adverse but realistic combination of service loads and, their arrangement, by elastic analysis, using a load, factor of 1.0. Table 6 gives recommended limits of, deflections for certain structural members and systems., Circumstances may arise where greater or lesser values, would be more appropriate depending upon the nature, of material in element to be supported (vulnerable to, cracking or not) and intended use of the structure, as, required by client., , and, , Unless specified otherwise, partial safety factor for, loads, y~,of value equal to unity shall be used for all, loads leading to serviceability limit states to check the, adequacy of the structure under serviceability limit, states., 5.6.1 Dejection, The deflection under serviceability, , loads of a building, , Table 6 Deflection, Type of, , Deflection, , DesignLoad, , Limits, Maximum, Deflection, , Supporthtg, , Member, , Building, , (1), , (4), , (3), , (2), , Live load/ Whrd load, , Elastic cladding, , Purlinsand Girts, [, , t,iVC, , load, , LNe load, , Simplespan, Cantilever span, , (6), , (5), , Brittle cladding, , Span/150, Span/l 80, , Elastic cladding, , Span/240, , Brittle cladding, , Spatr/300, , Elastic cladding, , Span/120, , Brittle cladding, , Span/150, , Profiled Metal Sheeting, , Sparr/180, , Plastered Sheeting, , Sparr1240, , L!ve load/Wind load, , Rafter supporting, , Crane load (Manual, operation), , Gantry, , Crane, , Spaa/500, , Crane load (Electric, operation up to 50 t), , Gantry, , Crane, , Spanl150, , Gantry, , Crane, , Span/l 000, , Elastic cladding, , Height/l 50, , Masonry/Brittle cladding, , Height/240, , Crane (absolute), , SpanMOO, , Relative displacement, between rails supporting, crane, , IOmm, , Gantry (Elastic cladding;, pendent operated), , Height/200, , Gantry (Brittle cladding; cab, operated), , Height/400, , Elements not susceptible to, cracking, , Sparr/300, , Elements susceptible to, cracking, , Spsm/360, , Elements not susceptible to, cracking, , Span/l 50, , Elements susceptible to, cracking, , Span/180, , Elastic cladding, , Height/300, , Brittle cladding, , Height/500, , Crane load (Electric, , operationover 50 t), No cranes, , Crane + wind, , Crane+wind, , Live load, , Live load, , Whrd, Wind, , Column, , Gantry (lateral), , Column/frame, , Floor and Roof, , Cantilever, , Building, Inter storey drift, , 31, , —, , Storey height/300

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IS 800:2007, 5.6.1.1 Where the deflection due to the combination, of dead load and Iive load is likely to be excessive,, consideration should be given to pre-camber the beams,, trusses and girders. The value of desired camber shall, be specified in design drawing. Generally, for spans, greater than 25 m, a camber approximately equal to, the deflection due to dead loads plus half the live load, may be used. The deflection of a member shall be, calculated without considering the impact factor or, dynamic effect of the loads on deflection. Roofs, which, are very flexible, shall be designed to withstand any, additional load that is likely to occur as a result of, pending of water or accumulation of snow or ice., , DESIGN, , 6.1 Tension Members, Tension members are linear members in which axial, forces act to cause elongation (stretch). Such members, can sustain loads upto the ultimate load, at which stage, they may fail by rupture at a critical section. However,, if the gross area of the member yields over a major, portion of its length before the rupture load is reached,, the member may become non-functional, due to, excessive elongation. Plates and other rolled sections, in tension may also fail by block shear of end bolted, regions (see 6.4.1)., , 5.6.2 Vibration, , The factored design tension 1“, in the members, satisfy the following requirement:, , Suitable provisions in the design shall be made for, the dynamic effects of live loads, impact loads and, vibrdti on due to machinery operating loads. In severe, cases, possibility, of resonance,, fatigue, or, unacceptable, vibrations, shall be investigated., Unusually flexible structures (generally the height, to effective width of lateral load resistance system, exceeding, 5:1) shall be investigated, for lateral, vibration, under dynamic wind loads. Structures, subjected to large number of cycles of loading shall, be designed against fatigue failure, as specified in, Section 13. Floor vibration effect shall be considered, using specialist literature (see Annex C),, , where, , T~ = design strength of the member., The design strength of a member under axial tension,, T~,is the lowest of the design strength due to yielding, of gross section, T~grupture strength of critical section,, T~n,and block shear T~~,given in 6.2, 6.3 and 6.4,, respectively., 6.2 Design Strength, , b), , Degree of exposure,, , c), , Shape of the member and the structural detail,, , d), , Protective measure, and, , e), , Ease of maintenance., , Due to Yielding of Gross Section, , The design strength of members under axial tension,, T~~,as governed by yielding of gross section, is given, by, , Factors that affect the durability of the buildings, under, conditions relevant to their intended life, are listed, below:, Environment,, , shall, , T<T~, , 5.6.3 Durabi[i(y, , a), , SECTION, 6, OF TENSION MEMBERS, , Tdg= Agfy Mno, where, f,, , = yield stress of the material,, , A~ = gross area of cross-section,, , and, , y~o = partial safety factor for failure in tension by, yielding (see Table 5)., , 5.6.3.1 The durability of steel structures shall be, ensured by following recommendations, in Section 15., Specialist literature may be referred to for more detailed, and additional information in design for durability., , 6.3 Design, Section, , Strength, , Due to Rupture, , of Critical, , 6.3.1 Plates, The design strength in tension of a plate, T~n, as, governed by rupture of net cross-sectional area, An, at, the holes is given by, , 5.6.4 Fire Resistance, Fire resistance of a steel member is a function of its, mass, its geometry, the actions to which it is subjected,, its structural, support condition,, fire protection, measures adopted and the fire to which it is exposed., Design provisioris to resist fire are briefly discussed in, Section 16. Specialist literature may be referred to for, more detailed information in design of fire resistance, of steel structures., , T~n= 0.9 AnfU/ ‘y~,, where, ‘Yml= partial safety factor for failure at ultimate, stress (see Table 5),, , 32, , f“, , = ultimate stress of the material, and, , An, , = net effective area of tbe member given by,

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.. ._,_,, ____, , IS 800:2007, , An= b-rid,, [, , LC = length of the end connection,, , that is the, distance between the outermost bolts in the, end joint measured along the load direction, or length of the weld along the load, direction., , 1, , + ~$-, , t, , it, , where, , b, t = width, , and thickness, respective y,, , of, , the, , plate,, , For preliminary sizing, the rupture strength, section may be approximately taken as:, , of net, , d~ = diameter of the bolt hole (2 mm in addition, to the diameter of the, directly punched holes),, , = gauge length between, , g, , hole, in case the, where, the bolt holes,, , as, , =, , number of bolt holes in the critical section,, and, , An, , = net area of the total cross-section;, , subscript for summation, , AgO = gross area of the outstanding, , = staggered-pitch, , length between line of bolt, holes, as shown in Fig. 5,, , P,, n=, i=, , 0.6 for one or two bolts, 0.7 for three bolts, and 0.8 for four or more bolts along the, length in the end connection or equivalent, weld length;, , cf., , shown in Fig. 5,, , An, = net area of the connected, , of all the inclined, , ., , t, , leg;, leg; and, , thickness of the leg., , Itv, , r], , w, , --. .-k--———, ------+ET, , 4, , L—-—.—--—————————, , J, , -.-Yd, , bs=w+w,, , 2, , b~=w, -t, , FIG. 6 ANGLESWITHSINGLELEG CONNECTIONS, 6.3,4 Other Section, , FIG. 5 PLATESWITHBOLTSHOLES IN TENSION, , The rupture strength,, Tdn,of the double angles,, channels, I-sections and other rolled steel sections,, connected by one or more elements to an end gusset is, also governed by shear lag effects. The design tensile, strength of such sections as governed by tearing of net, section may also be calculated using equation in 6.3.3,, where ~ is calculated based on the shear lag distance,, b,, taken from the farthest edge of the outstanding leg, to the nearest bolt/weld line in the connected leg of, the cross-section., , 6.3.2 Threaded Rods, The design strength of threaded rods in tension, Tdn,as, governed by rupture is given by, , Tdn= 0.9 An ful ym,, where, , Am = net root area at the threaded section., 6.3.3 Single Angles, , 6.4 Design Strength, The rupture strength of an angle connected through, one leg is affected by shear lag. The design strength,, Tdn,as governed by rupture at net section is given by:, , Due to Block Shear, , The strength as governed by block shear at an end, connection of plates and angles is calculated as given, in 6.4.1., , 7’dn=0.9 AnC~u/ ‘y~l + ~ A~OfY/Y~O, 6.4.1 Bolted Connections, , where, , Td~of connection, , The block shear strength,, taken as the smaller of,, , shall be, , where, w, , = outstand leg width,, , b,, , = shear lag width, as shown in Fig. 6, and, , or, Td~= (0.944,. f. /( $, , 33, , ~ml) + Atgfy %0 )

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IS 800:2007, where, , where, , Av~,Avn= minimum gross and net area in shear along, , A., , = effective, , area as defined, , bolt line parallel, to external, force,, respectively, (1-2 and 3-4 as shown in, Fig. 7A and 1-2 as shown in Fig. 7B),, , sectional, in 7.3.2, and, , Id, , = design compressive, as per 7.1.2.1., , stress, obtained, , At~,A,fl = minimum, , gross and net area in tension, from the bolt hole to the toe of the angle,, end bolt line, perpendicular to the line of, force, respectively, (2-3 as shown in, Fig. 7B), and, , ~u,~Y, , 7.1.2.1 The design compressive stress, ~d, of axially, loaded compression members shrdl be calculated using, the following equation:, f, /ymo, f.,, , = ultimate and yield stress of the material,, respectively., , = Xfy/Ymo, , =, , ~ fy/Yti, , (j+[&-q’, , 6.4.2 Welded Connection, 0.5 [1 + a (x – 0.2)+ az], , The block shear strength, Td~ shall be checked for, welded end connections, by taking an appropriate, , non-dimensional, , effective slenderness, , ratio, , section in the member around the end weld, which can, shear off as a block., , DESIGN, , SECTION 7, OF COMPRESSION, , X2 E, , MEMBERS, Xx, , 7.1 Design Strength, , where, , 7.1.1 Common hot rolled and built-up steel members, used for carrying axial compression, usually fail by, flexural buckling. The buckling strength of these, members is affected by residual stresses, initial bow, and accidental eccentricities of load. To account for, all these factors, the strength of members subjected to, axial compression is defined by buckling class a, b, c,, or d as given Table 7., 7.1.2 The design compressive, is given by:, , = Euler buckling stress = (KL/\2, ( /r], , KL/r = effective slenderness, , ratio or ratio, KL to, of effective, length,, appropriate radius of gyration, E, , a=, , imperfection, Table 7;, , x’=, , stress reduction factor (see Table 8), for different, buckling, class,, slenderness ratio and yield stress, , strength Pd, of a member, , P<Pd, , =, , where, , AmO =, , P~ = A,fCd, , --EEm-4—0[, , E–, +—*, —-, , I, , “-”~, ‘L’, , 7A Plate, , 7B Angle, FIG. 7 BLOCKSHEARFAILURE, 34, , in, , partial safety factor for material, strength., , --*--72, I, 4*, *3, I, 1, , given, , [o+($z~a’r’], ,, , 1, , -, , factor, , —

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. ._., _,, , ., , b., , IS 800:2007, can be assessed, the effective length, KL can be, calculated on the basis of Table 11. Where frame, analysis does not consider the equilibrium of a framed, structure in the deformed shape (second-order analysis, or advanced, analysis),, the effective, length of, compression members in such cases can be calculated, using the procedure given in D-1. The effective length, of stepped column in single storey buildings can be, calculated using the procedure given in D-2., , NOTE — Calculated values of design compressive stress,.fi~, for different buckling classes are given in Table 9., , 7.1.2.2 The classification of different sections under, different buckling class a, b, c or d, is given in Table, 10. The stress reduction factor X, and the design, compressive stress~,~, for different buckling class, yield, stress, and effective slenderness ratio is given in Table, 8 for convenience., The curves corresponding, to, different, buckling, class are presented, in nondimensional form, in Fig. 8., Table 7 Imperfection, (Chzuse.s7.l.l, , Factor,, , 7.2.3 Eccentric Beam Connection, In cases where the beam connections are eccentric in, plan with respect to the axes of the column, the same, conditions of restraint as in concentric connection shall, be deemed to apply, provided the connections, are, carried across the flange or web of the columns as the, case may be, and the web of the beam lies within, or in, direct contact with the column section, Where practical, difficulties prevent this, the effective length shall be, taken as equal to the distance between points of, restraint, in non-sway frames., , et, , arzd7.1.2.1), , Buckling Class, , a, , b, , c, , d, , a, , 0.21, , 0.34, , 0.49, , 0.76, , 7.2 Effective Length of Compression, , Members, , 7.2.1 The effective length KL, is calculated from the, the, actual length L, of the member, considering, rotational, and relative, translational, boundary, conditions at the ends. The actual length shall be taken, as the length from centre-to-centre of its intersections, with the supporting members in the plane of the, buckling deformation. In the case of a member with a, free end, the free standing length from the center of, the intersecting member at the supported end, shall be, taken as the actual length., , 7.2.4 Compression Members in Trusses, In the case of bolted, riveted or welded trusses and, braced frames, the effective, length, KL, of the, compression members shall be taken as 0.7 to 1.0 times, the distance between centres of connections, depending, on the degree of end restraint provided. In the case of, members of trusses, buckling in the plane perpendicular, to the plane of the truss, the effective length, KL shall, be taken as the distance between the centres of, intersection. The design of angle struts shall be as, specified in 7.5., , 7.2.2 Effective Length, Where the boundary conditions in the plane of buckling, , 1.0, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0, , 0, , 0.5, , 1.0, , 1,5, , 2:0, , FIG. 8 COLUMNBUCKLINGCURVES, 35, , 2;5, , 3;0

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a00, Table 8(a) Stress Reduction, , Factor,, , x for Column Buckling, , 0, 0, .., N, =, , Class a, , (Clauses 7.1.2.1 and 7.1.2.2), Yield Stress,J, , KM, , L, , (MPa), , 1., , 200, , 210, , 220, , 230, , 240, , 250, , 260, , 280, , 300, , 320, , 340, , 360, , 380, , 400, , 420, , 450, , 480, , 510, , 540, , 10, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 20, , 1.000, , 0.999, , 0.998, , 0.997, , 0.995, , 0.994, , 0.993, , 0.993, , 0.990, , 0.988, , 0.986, , 0.984, , 0.983, , 0.981, , 0.979, , 0.977, , 0.975, , 0.972, , 0.970, , 30, , 0.977, , 0.975, , 0.974, , 0.972, , 0.970, , 0.969, , 0.967, , 0.965, , 0.961, , 0.957, , 0.954, , 0.951, , 0.948, , 0.946, , 0.943, , 0.938, , 0.934, , 0.930, , 0.925, , 40, , 0.952, , 0.949, , 0,947, , 0.944, , 0.942, , 0.939, , 0.937, , 0.934, , 0.926, , 0.921, , 0.916, , 0.911, , 0.906, , 0.901, , 0.896, , 0.888, , 0.881, , 0.873, , 0.865, , 50, , 0.923, , 0.919, , 0.915, , 0.911, , 0.908, , 0.904, , 0.900, , 0.896, , 0.884, , 0.876, , 0.867, , 0.859, , 0.851, , 0.842, , 0.834, , 0.820, , 0.807, , 0.794, , 0.780, , 60, , 0.888, , 0.883, , 0.877, , 0.871, , 0.865, , 0.859, , 0.853, , 0.847, , 0.828, , 0.816, , 0.803, , 0.790, , 0.777, , 0.763, , 0.750, , 0.730, , 0.710, , 0.690, , 0.671, , 70, , 0.846, , 0.837, , 0.829, , 0.820, , 0.811, , 0.803, , 0.794, , 0.785, , 0.758, , 0.740, , 0.722, , 0.703, , 0.686, , 0.668, , 0.651, , 0.626, , 0.602, , 0.579, , 0.557, , 80, , 0.793, , 0.781, , 0.769, , 0.757, , 0.746, , 0.734, , 0.722, , 0.710, , 0.675, , 0.653, , 0.631, , 0.610, , 0.589, , 0.570, , 0.551, , 0.525, , 0.501, , 0.478, , 0.458, , 90, , 0.730, , 0.715, , 0.700, , 0.685, , 0.671, , 0.657, , 0.643, , 0.628, , 0.590, , 0.565, , 0.542, , 0.520, , 0.500, , 0.481, , 0.463, , 0.439, , 0.416, , 0.396, , 0.377, , 100, , 0.661, , 0.644, , 0.627, , 0.610, , 0.594, , 0.579, , 0.564, , 0.549, , 0.510, , 0.486, , 0.463, , 0.443, , 0.424, , 0.407, , 0.390, , 0.368, , 0.348, , 0.331, , 0.314, , I 10, , 0.591, , 0.573, , 0.555, , 0.538, , 0.522, , 0.507, , 0.492, , 0.478, , 0.440, , 0.418, , 0.397, , 0.379, , Q.362, , 0.346, , 0.332, , 0.312, , 0.295, , 0.279, , 0.265, , 120, , 0.525, , 0.507, , 0.489, , 0.473, , 0.458, , 0.443, , 0.429, , 0.416, , 0.381, , 0.361, , 0.343, , 0.326, , 0.311, , 0.297, , 0.284, , 0.267, , 0.252, , 0.238, , 0.226, , 130, , 0.466, , 0.448, , 0.432, , 0.416, , 0.402, , 0.388, , 0.376, , 0.364, , 0.332, , 0.314, , 0.298, , 0.283, , 0.269, , 0.257, , 0.246, , 0.231, , 0.217, , U.206, , 0.195, , 0.275, , 0.260, , 0.247, , 0.235, , 0.224, , 0.214, , 0.201, , 0.189, , 0.179, , 0.170, , 0.177, , 0.166, , 0.157, , 0.149, , 0.157, , 0.147, , 0.139, , 0.132, , 140, , 0.413, , 0.397, , 0.382, , 0.368, , 0.355, , 0.342, , 0.331, , 0.320, , 0.291, , 150, , 0.368, , 0.353, , 0.339, , 0.326, , 0.314, , 0.303, , 0.293, , 0.283, , 0.257, , 0.243, , 0.229, , 0.218, , 0.207, , 0.197, , 0.189, , 160_, , 0.329, , 0.316, , 0.303, , 0.291, , 0.280, , 0.270, , 0.261, , 0.252, , 0.229, , 0.215, , 0.204, , 0.193, , 0.184, , 0.175, , 0.167, , 0.192, , 0.182, , 0.172, , 0.164, , 0.156, , 0.149, , 0.140, , 0.131, , 0.124, , 0.117, , 0.173, , 0.163, , 0.155, , 0.147, , 0.140, , 0.134, , 0.125, , 0.118, , 0.111, , 0.105, , 170, , 0.296, , 0.283, , 0.272, , 0.261, , 0.251, , 0.242, , 0.233, , 0.225, , 0.204, , 180, , 0.267, , 0.255, , 0.245, , 0.235, , 0.226, , 0.218, , 0.210, , 0.203, , 0.184, , 190, , 0.242, , 0.231, , 0.222, , 0.213, , 0.205, , 0.197, , 0.190, , 0.183, , 0.166, , 0.156, , 0.147, , 0.140, , 0.133, , 0.126, , 0.121, , 0.113, , 0.106, , 0.100, , 0.095, , 200, , 0.220, , 0.210, , 0.202, , 0.193, , 0.186, , 0.179, , 0.172, , 0.166, , 0.151, , 0.142, , 0.134, , 0.127, , 0.120, , 0.115, , 0.109, , 0.102, , 0.096, , 0.091, , 0,086, , 210, , 0.201, , 0.192, , 0.184, , 0.177, , 0.170, , 0.163, , 0.157, , 0.152, , 0.137, , 0,129, , 0.122, , 0.115, , 0.110, , 0.104, , 0.099, , 0.093, , 0.087, , 0.083, , 0.078, , 220, , 0.184, , 0.176, , 0.169, , 0.162, , 0.155, , 0.149, , 0.144, , 0.139, , 0.126, , 0.118, , 0.111, , 0.106, , 0.100, , 0.095, , 0.091, , 0.085, , 0.080, , 0.075, , 0.071, , 0.108, , 0.102, , 0.097, , 0.092, , 0.088, , 0.083, , 0.078, , 0.073, , 0.069, , 0.065, , 0.085, , 0.081, , 0.077, , 0.072, , 0.068, , 0.064, , 0.060, , 0.078, , 0.074, , 0.071, , 0.066, , 0.062, , 0.059, , 0.056, , 230, , 0.170, , 0.162, , 0.155, , 0.149, , 0.143, , 0.137, , 0.132, , 0.128, , 0.115, , 240, , 0.157, , 0.149, , 0.143, , 0.137, , 0.132, , 0.127, , 0.122, , 0.118, , 0.106, , 0.100, , 0.094, , 0.089, , 250, , 0.145, , 0.138, , 0.132, , 0.127, , 0.122, , 0.117, , 0.113, , 0.109, , 0.098, , 0.092, , 0.087, , 0.082

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Table 8(b) Stress Reduction, , Factor,, , ~ for Column Buckling, , Class b, , (Clauses 7.1.2.1 and 7. 1.2.2), Yield Stress, A, , KL/r, , (MPa), , 4, , 200, , 10, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , I.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1,000, , I.000, , 1.000, , 20, , 1.000, , 0.998, , 0.996, , 0.994, , 0.993, , 0.991, , 0.990, , 0.986, , 0.983, , 0.981, , 0.978, , 0.975, , 0.972, , 0.970, , 0.967, , 0.963, , 0.960, , 0.956, , 0.953, , 0.924, , 0.920, , 0.915, , 0.91 I, , 0.904, , 0.898, , 0.892, , 0.886, , 210, , 220, , 230, , 240, , 250, , 260, , 280, , 300, , 320, , 340, , 360, , 380, , 400, , 420, , 450, , 480, , 510, , 540, , 30, , 0.963, , 0.961, , 0.958, , 0.955, , 0.953, , 0.950, , 0.948, , 0.943, , 0.938, , 0.933, , 0.929, , 40, , 0.925, , 0.921, , 0.917, , 0.913, , 0.909, , 0.906, , 0.902, , 0.895, , 0.887, , 0.880, , 0.873, , 0.866, , 0.859, , 0.852, , 0.845, , 0.835, , 0.825, , 0.815, , 0.805, , 50, , 0,883, , 0.877, , 0.872, , 0.866, , 0.861, , 0.855, , 0.850, , 0.839, , 0.829, , 0.818, , 0.808, , 0.798, , 0.787, , 0.777, , 0.767, , 0.752, , 0.737, , 0.722, , 0.708, , 60, , 0.835, , 0.827, , 0.820, , 0.812, , 0.805, , 0.798, , 0.790, , 0.775, , 0.761, , 0.746, , 0.732, , 0.718, , 0.704, , 0.691, , 0.677, , 0.657, , 0.638, , 0.620, , 0.602, , 70, , 0.781, , 0.771, , 0.761, , 0.751, , 0.742, , 0.732, , 0.722, , 0.703, , 0.685, , 0.667, , 0.649, , 0.632, , 0.615, , 0.599, , 0.584, , 0.561, , 0.540, , 0.520, , 0.502, , 80, , 0.721, , 0.709, , 0.697, , 0.685, , 0.673, , 0.661, , 0.650, , 0.627, , 0.606, , 0.585, , 0.566, , 0.547, , 0.529, , 0.512, , 0.496, , 0.474, , 0.453, , 0.434, , 0.416, , 90, , 0.657, , 0.643, , 0.629, , 0.615, , 0.602, , 0.589, , 0.576, , 0.552, , 0.530, , 0.508, , 0.488, , 0.470, , 0.452, , 0.436, , 0.421, , 0.400, , 0.380, , 0.363, , 0.346, , 100, , 0.593, , 0.577, , 0.562, , 0.548, , 0.534, , 0.520, , 0.507, , 0.483, , 0.461, , 0.440, , 0.421, , 0.403, , 0.387, , 0.372, , 0.358, , 0.339, , 0.321, , 0.306, , 0.291, , 110, , 0.531, , 0.515, , 0.500, , 0.485, , 0.471, , 0.458, , 0.445, , 0.422, , 0.401, , 0.381, , 0.364, , 0.348, , 0.333, , 0.319, , 0.306, , 0.289, , 0.274, , 0.260, , 0.247, , 120, , 0.474, , 0.458, , 0.443, , 0.429, , 0.416, , 0.403, , 0.391, , 0.370, , 0.350, , 0.332, , 0.316, , 0.30 I, , 0.288, , 0.276, , 0.265, , 0.249, , 0.236, , 0.223, , 0.212, , 130, , 0.423, , 0.408, , 0.394, , 0.380, , 0.368, , 0.356, , 0.345, , 0.325, , 0.307, , 0.291, , 0.276, , 0.263, , 0.251, , 0.240, , 0.230, , 0.217, , 0.204, , 0.194, , 0.184, , 140, , 0.378, , 0.364, , 0.350, , 0.338, , 0.327, , 0.316, , 0.306, , 0.287, , 0.271, , 0.256, , 0.243, , 0.23 I, , 0.221, , 0.21 I, , 0.202, , 0.190, , 0. I79, , 0.169, , 0.161, , 150, , 0.339, , 0.325, , 0.313, , 0.302, , 0.291, , 0.281, , 0.272, , 0.255, , 0.241, , 0.227, , 0.215, , 0.205, , 0.195, , 0.186, , 0.178, , 0.167, , 0.158, , 0.149, , 0.142, , 160, , 0.305, , 0.292, , 0.281, , 0.271, , 0.261, , 0.252, , 0.243, , 0.228, , 0.215, , 0.203, , 0.192, , 0.182, , 0.L74, , o.166, , 0.158, , 0.149, , 0.140, , 0.133, , 0.126, , 170, , 0.275, , 0.264, , 0.253, , 0.244, , 0.235, , 0.227, , 0.219, , 0.205, , 0.193, , 0.182, , 0.172, , 0.163, , 0.155, , 0.148, , 0.142, , 0.133, , 0.125, , 0.118, , 0.112, , 0.147, , 0.140, , 0.133, , 0.128, , 0.120, , 0.113, , 0.106, , 0.101, , 0.108, , 180, , 0.249, , 0.239, , 0.229, , 0.220, , 0.212, , 0.205, , 0.198, , 0.185, , 0.174, , 0.164, , 0.155, , 190, , 0.227, , 0.217, , 0.208, , 0.200, , 0.193, , 0.186, , 0.179, , 0.168, , 0.157, , 0.148, , 0.140, , 0.133, , 0.127, , 0.121, , 0.115, , 0.102, , 0.096, , 0.091, , 200, , 0.207, , 0.198, , 0.190, , 0.183, , 0.176, , 0.169, , 0.163, , 0.153, , 0.143, , 0.135, , 0.128, , 0.121, , 0.[15, , 0.110, , 0.105, , 0.098, , 0.092, , 0.087, , 0.083, , 2}0, , 0.190, , 0.182, , 0.174, , 0.167, , 0.161, , 0.155, , 0.149, , 0.140, , 0.131, , 0.123, , 0.117, , 0.110, , 0.105, , 0.100, , 0.096, , 0.090, , 0.084, , 0.080, , 0.075, , 220, , 0.174, , 0.167, , 0.160, , 0.154, , 0.148, , 0.142, , 0.137, , 0.128, , 0.120, , 0.113, , 0.107, , 0.101, , 0.096, , 0.092, , 0.088, , 0.082, , 0.077, , 0.073, , 0.069, , 230, , 0.161, , 0.154, , 0.147, , 0.141, , 0.136, , 0.131, , 0.126, , 0.118, , 0.111, , 0.104, , 0.098, , 0.093, , 0.088, , 0.084, , 0.080, , 0.075, , 0.071, , 0.067, , 0.063, , 240, , 0.149, , 0.142, , 0.136, , 0.131, , 0.126, , 0.121, , 0.117, , 0.109, , 0.102, , 0.096, , 0.091, , 0.086, , 0.082, , 0.078, , 0.074, , 0.070, , 0.065, , 0.062, , 0.058, , 250, , 0.138, , 0.132, , 0.126, , 0.121, , 0.117, , 0.112, , 0.108, , 0.101, , 0.095, , 0.089, , 0.084, , 0.080, , 0.076, , 0.072, , 0.069, , 0.064, , 0.060, , 0.057, , 0.054, , E, 00, , 0, 0

Page 44 :
Table 8(c) Stress Reduction, , Factor,, , ~ for Column Buckling, , %, m, o, 0, .., , Class c, , (Clauses 7.1.2.1 and 7.1.2.2), Yield Stress,, , KLlr, , 4, , f, (MPa), , 200, , 210, , 220, , 230, , 10, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 20, , 0.999, , 0.997, , 0.994, , 0.992, , 0.990, , 0.987, , 0.985, , 0.981, , 0.976, , 0.972, , 0,968, , 0.964, , 30, , 0.948, , 0.944, , 0.941, , 0.937, , 0.933, , 0,930, , 0.926, , 0.920, , 0.913, , 0.907, , 0.901, , 0.895, , 0.S89, , 0.883, , 0.877, , 40, , 0.896, , 0.891, , 0.885, , 0.880, , 0.875, , 0.870, , 0.866, , 0.856, , 0.847, , 0.838, , 0.829, , 0.820, , 0.812, , 0.803, , 0.795, , 240, , 250, , 260, , 280, , 300, , 320, , 340, , 360, , 400, , 420, , 450, , 480, , 1.000, , 1.000, , 1.000, , I.000, , 1.000, , 1.000, , I.000, , 0.961, , 0.957, , 0.953, , 0.948, , 0.943, , 0.938, , 0.933, , 0.869, , 0.861, , 0.853, , 0.845, , 0.783, , 0.771, , 0.760, , 0.748, , 380, , 510, , 540, , 50, , 0.841, , 0.834, , 0.827, , 0.821, , 0.814, , 0.807, , 0.801, , 0.788, , 0.776, , 0.763, , 0.752, , 0.740, , 0.729, , 0.717, , 0.706, , 0.690, , 0.675, , 0.660, , 0.645, , 60, , 0.783, , 0.774, , 0.765, , 0.757, , 0.748, , 0.740, , 0.732, , 0.716, , 0.700, , 0.685, , 0.670, , 0.656, , 0.642, , 0.628, , 0.615, , 0.596, , 0.578, , 0.561, , 0.544, , 70, , 0.722, , 0.711, , 0.700, , 0.690, , 0.680, , 0.670, , 0.660, , 0.641, , 0.623, , 0.605, , 0.588, , 0.572, , 0.557, , 0.542, , 0.528, , 0.508, , 0.489, , 0.471, , 0.454, , 80, , 0.659, , 0.646, , 0.634, , 0.622, , 0.611, , 0.600, , 0.589, , 0.568, , 0.548, , 0.529, , 0.512, , 0.495, , 0.479, , 0.464, , 0.450, , 0.430, , 0.412, , 0.395, , 0.379, , 90, , 0.596, , 0.583, , 0.569, , 0.557, , 0.544, , 0.533, , 0.521, , 0.499, , 0.479, , 0.460, , 0.443, , 0.426, , 0.411, , 0.397, , 0.383, , 0.365, , 0.348, , 0.332, , 0.318, , I00, , 0.536, , 0.522, , 0.508, , 0.495, , 0.483, , 0.47 I, , 0.459, , 0.438, , 0.418, , 0.400, , 0.384, , 0.368, , 0.354, , 0.341, , 0.328, , 0.3I 1, , 0.296, , 0.282, , 0.269, , 110, , 0.480, , 0.466, , 0.453, , 0.440, , 0.428, , 0.416, , 0.405, , 0.385, , 0.366, , 0.349, , 0.333, , 0.3 I9, , 0.306, , 0.294, , 0.283, , 0.268, , 0.254, , 0.242, , 0.230, , 120, , 0.430, , 0.416, , 0.403, , 0.391, , 0..379, , 0.368, , 0.358, , 0.339, , 0.321, , 0.306, , 0.291, , 0.278, , 0.267, , 0.256, , 0.246, , 0.232, , 0.220, , 0.209, , 0.199, , 130, , 0.385, , 0.372, , 0.360, , 0.348, , 0.337, , 0.327, , 0.317, , 0.299, , 0.283, , 0.269, , 0.256, , 0.244, , 0.234, , 0.224, , 0.215, , 0.203, , 0.192, , 0.182, , 0.173, , 140, , 0.346, , 0.333, , 0.322, , 0.311, , 0.301, , 0.291, , 0.282, , 0.266, , 0.25 I, , 0.238, , 0.227, , 0.216, , 0.206, , 0.197, , 0.189, , 0.178, , 0.168, , 0.160, , 0.152, , 150, , 0.31 I, , 0.300, , 0.289, , 0.279, , 0.269, , 0.261, , 0.252, , 0.237, , 0.224, , 0.212, , 0.202, , 0.192, , 0.183, , 0.175, , 0.168, , 0.158, , 0.149, , 0.141, , 0.134, , 160, , 0.28 I, , 0.270, , 0.260, , 0.251, , 0.242, , 0.234, , 0.227, , 0.213, , 0.201, , 0,190, , 0.180, , 0.172, , 0.164, , 0.156, , 0.150, , 0.141, , 0.133, , 0.126, , 0.120, , 170, , 0.255, , 0.245, , 0.236, , 0.227, , 0.219, , 0.212, , 0.205, , 0.192, , 0.181, , 0.171, , 0.162, , 0.154, , 0.147, , 0.140, , 0.134, , 0.126, , 0.119, , 0.113, , 0.107, , 180, , 0.232, , 0.223, , 0.214, , 0.206, , 0.199, , 0.192, , 0.186, , 0.174, , 0.164, , 0.155, , 0.147, , 0.139, , 0.133, , 0.127, , 0.121, , 0.114, , 0.107, , 0.102, , 0.096, , 0.181, , 0.175, , 0.169, , 0.158, , 0.149, , 0.140, , 0.133, , 0.126, , 0.120, , 0.115, , 0.110, , 0.103, , 0.097, , 0.092, , 0.087, , 0.136, , 0.128, , 0.121, , 0.115, , 0.110, , 0.105, , 0.100, , 0.094, , 0.089, , 0.084, , 0.079, , 0.124, , 0.117, , 0.111, , 0.105, , 0.100, , 0.096, , 0.092, , 0.086, , 0.081, , 0.076, , 0.072, , 190, , 0.212, , 0.203, , 0.195, , 0.188, , 200, , 0.194, , 0.186, , 0.179, , 0.172, , 0.166, , 0.160, , 0.154, , 0.144, , 210, , 0.178, , 0.171, , 0.164, , 0.158, , 0.152, , 0.146, , 0.141, , 0.132, , 220, , O.!64, , 0.157, , 0.151, , 0.145, , 0. I40, , 0.135, , 0.130, , 0.122, , 0.114, , 0.108, , 0.102, , 0.097, , 0.092, , 0.088, , 0.084, , 0.079, , 0.074, , 0.070, , 0.066, , 230, , 0.152, , 0.145, , 0.140, , 0.134, , 0.129, , 0.124, , 0.120, , 0.112, , 0.105, , 0.099, , 0.094, , 0.089, , 0.085, , 0.081, , 0.077, , 0.073, , 0.068, , 0.065, , 0.061, , 240, , 0.141, , 0.135, , 0.129, , 0.124, , 0.120, , 0.115, , 0.111, , 0.104, , 0.098, , 0.092, , 0.087, , 0.082, , 0.078, , 0.075, , 0.071, , 0.067, , 0.063, , 0.060, , 0.056, , 250, , 0.131, , 0.125, , 0.120, , 0.115, , 0.111, , 0. I07, , 0.103, , 0.096, , 0.090, , 0.085, , 0.081, , 0.076, , 0.073, , 0.069, , 0.066, , 0.062, , 0.058, , 0.055, , 0.052

Page 45 :
Table 8(d) Stress Reduction, , Factor,, , ~ for Column, , Buckling, , C lass d, , (Clauses 7.1.2.1 and 7.1 .2.2), Yield Stress, JY(MPa), , IA, , 4, , 200, , 210, , 220, , 230, , 240, , 10, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , I.000, , 1.000, , 20, , 0.999, , 0.995, , 0.991, , 0.988, , 0.984, , 0.980, , 0.977, , 0.970, , 0.964, , 0.958, , 0.952, , 0.946, , 250, , 260, , 280, , 300, , 320, , 340, , 360, , 400, , 420, , 450, , 480, , 510, , 540, , 1.000, , 1.000, , 1.000, , 1.000, , 1.000, , i .000, , 1.000, , 0.940, , 0.935, , 0.930, , 0.922, , 0.915, , 0.908, , 0.901, , 380, , 30, , 0.922, , 0.916, , 0.91 I, , 0.906, , 0.901, , 0.896, , 0.891, , 0.881, , 0.872, , 0.863, , 0.855, , 0.847, , 0.839, , 0.831, , 0.823, , 0.813, , 0.802, , 0.792, , 0.782, , 40, , 0.848, , 0.841, , 0.834, , 0.828, , 0.821, , 0.815, , 0.808, , 0.796, , 0.784, , 0.773, , 0.762, , 0.751, , o.74i, , 0.731, , 0.721, , 0.707, , 0.694, , 0.681, , 0.668, , 50, , 0.777, , 0.768, , 0.760, , 0.752, , 0.744, , 0.736, , 0.728, , 0.713, , 0.699, , 0.685, , 0.672, , 0.659, , 0.647, , 0.635, , 0.624, , 0.608, , 0.592, , 0.577, , 0.563, , 60, , 0.707, , 0.697, , 0.687, , 0.678, , 0.668, , 0.659, , 0.651, , 0.634, , 0.617, , 0.602, , 0.587, , 0.573, , 0.560, , 0.547, , 0.535, , 0.517, , 0.501, , 0.486, , 0.471, , 70, , 0.640, , 0.629, , 0.618, , 0.607, , 0.597, , 0.587, , 0.578, , 0.559, , 0.542, , 0.526, , 0.510, , 0.496, , 0.482, , 0.469, , 0.456, , 0.439, , 0.423, , 0.408, , 0.394, , 80, , 0.576, , 0.564, , 0.553, , 0.542, , 0.531, , 0.521, , 0.511, , 0.492, , 0.474, , 0.458, , 0.442, , 0.428, , 0.414, , 0.402, , 0.390, , 0.373, , 0.358, , 0.344, , 0.330, , 90, , 0.517, , 0.505, , 0.493, , 0.482, , 0.471, , 0.461, , 0.451, , 0.432, , 0.415, , 0.399, , 0.384, , 0.370, , 0.357, , 0.345, , 0.334, , 0.319, , 0.304, , 0.292, , 0.280, , 00, , 0.464, , 0.451, , 0.440, , 0.428, , 0.418, , 0.408, , 0.398, , 0,380, , 0.363, , 0.348, , 0.334, , 0.321, , 0.309, , 0.298, , 0.288, , 0,274, , 0.261, , o,~49, , 0.239, , 10, , 0.416, , 0.404, , 0.392, , 0.381, , 0.371, , 0.361, , 0.352, , 0.335, , 0.319, , 0.305, , 0.292, , 0.281, , 0.270, , 0.259, , 0.250, , o.~37, , 0.226, , 0.215, , 0.206, , 20, , 0.373, , 0.361, , 0.350, , 0.340, , 0.330, , 0.321, , 0.313, , 0.297, , 0.282, , 0.269, , 0.257, , 0.246, , 0.236, , 0.227, , 0.219, , 0.207, , 0.197, , 0.187, , 0.179, , 30, , 0.336, , 0.325, , 0.314, , 0.305, , 0.295, , 0.287, , 0.279, , 0.264, , 0.251, , 0.239, , 0.228, , 0.218, , 0.209, , 0.200, , 0.193, , 0.182, , 0.173, , 0.164, , 0.157, , 40, , 0.303, , 0.292, , 0.283, , 0.274, , 0.265, , 0.257, , 0.250, , 0.236, , 0.224, , 0.213, , 0.203, , 0.194, , 0.185, , 0.178, , 0.171, , 0.161, , 0.153, , 0.145, , 0.138, , 50, , 0.274, , 0.264, , 0.255, , 0.247, , 0.239, , 0.231, , 0.224, , 0.212, , 0.201, , 0.190, , 0.181, , 0.173, , 0.165, , 0.159, , 0.152, , 0.144, , 0.136, , 0.129, , 0.123, , 60, , 0.249, , 0.240, , 0.231, , 0.223, , 0.216, , 0.209, , 0.203, , 0.191, , 0.181, , 0.171, , 0.163, , 0.155, , 0.149, , 0.142, , 0.137, , 0.129, , 0.122, , 0.116, , 0.110, , 70, , 0.227, , 0.218, , 0.210, , 0.203, , 0.196, , 0.190, , 0.184, , 0.173, , 0.164, , 0.155, , 0.147, , 0.140, , 0.134, , 0.128, , 0.123, , 0.116, , 0.110, , 0.104, , 0.099, , 80, , 0.207, , 0.199, , 0.192, , 0.185, , 0.179, , 0.173, , 0.167, , 0.157, , 0.149, , 0.141, , 0.134, , 0.127, , 0.122, , 0.1)6, , 0.111, , 0.105, , 0.099, , 0.094, , 0.089, , 90, , 0.190, , 0.183, , 0.176, , 0.169, , 0.164, , 0.158, , 0.153, , 0.144, , 0.136, , 0.128, , 0.122, , 0.116, , 0.111, , 0.106, , 0.101, , 0.095, , 0.090, , 0.085, , 0.081, , 00, , 0.175, , 0.168, , 0.162, , 0.156, , 0.150, , 0.145, , 0.140, , 0.132, , 0.124, , 0.118, , 0.112, , 0.106, , 0.101, , 0.097, , 0.093, , 0.087, , 0.082, , 0.078, , 0.074, , 10, , 0.161, , 0.155, , 0.149, , 0.143, , 0.138, , 0.134, , 0.129, , 0.121, , 0.114, , 0.108, , 0.102, , 0.097, , 0.093, , 0.089, , 0.085, , 0.080, , 0.075, , 0.071, , 0.068, , 20, , 0.149, , 0.143, , 0.138, , 0.133, , 0.128, , 0.123, , 0.119, , 0.112, , 0.105, , 0.100, , 0.094, , 0.090, , 0.086, , 0.082, , 0.078”, , 0.074, , 0.069, , 0.066, , 0.062, , 30, , 0.138, , 0.133, , 0.128, , 0.123, , 0.118, , 0.114, , 0.110, , 0.104, , 0.097, , 0.092, , 0.087, , 0.083, , 0.079, , 0.075, , 0.072, , 0.068, , 0.064, , 0.061, , 0.058, , 40, , 0.129, , 0.123, , 0.119, , 0.114, , 0.11o, , 0.106, , 0.103, , 0.096, , 0.090, , 0.085, , 0.081, , 0.077, , 0.073, , 0.070, , 0.067, , 0.063, , 0.059, , 0.056, , 0.053, , 50, , 0.120, , 0.115, , 0.110, , 0.106, , 0.102, , 0.099, , 0.095, , 0.089, , 0.084, , 0.079, , 0.075, , 0.071, , 0.068, , 0.065, , 0.062, , 0.058, , 0.055, , 0.052, , 0.049, , %, 00, 0, 0, .., , ~, o, 4

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Table 9(a) Design Compressive, , Stress,~C~ (MPa) for Column Buckling, , Class a, , E, m, o, 0, .., , (Ckzuse 7.1.2.1), Yield Stress, &, , KLlr, , J, , 200, , 210, , 220, , 230, , 240, , 250, , 260, , 280, , 300, , 320, , (MPa), 340, , 360, , 380, , 400, , 420, , 450, , 480, , 510, , 540, , 10, , 182, , 191, , 200, , 213, , 218, , 227, , 236, , 255, , 273, , 291, , 309, , 327, , 34 s, , 364, , 382, , 409, , 436, , 464, , 491, , 20, , 182, , 191, , 200, , 208, , 217, , 226, , 235, , 252, , 270, , 287, , 305, , 322, , 339, , 357, , 374, , 400, , 425, , 451, , 476, , 30, , 178, , 186, , 195, , 203, , 212, , 220, , 229, , 245, , 262, , 279, , 295, , 311, , 328, , 344, , 360, , 384, , 408, , 431, , 454, , 40, , 173, , 181, , 189, , 197, , 205, , 213, , 221, , 237, , 253, , 268, , 283, , 298, , 313, , 328, , 342, , 363, , 384, , 405, , 425, , 281, , 294, , 306, , 318, , 336, , 352, , 368, , 383, , 310, , 320, , 329, , 50, , 168, , 176, , 183, , 191, , 198, , 205, , 213, , 227, , 241, , 255, , 268, , 60, , 162, , 169, , 1’75, , 182, , 189, , I95, , 202, , 214, , 226, , 237, , 248, , 258, , 268, , 278, , 286, , 299, , 70, , 154, , 160, , 166, , 171, , 177, , 182, , I88, , 197, , 207, , 215, , 223, , 230, , 237, , 243, , 249, , 256, , 263, , 268, , 274, , 80, , I44, , 149, , 154, , 158, , 163, , 167, , 171, , 178, , 184, , 190, , 195, , 199, , 204, , 207, , 210, , 215, , 219, , 222, , 225, , 90, , 133, , I37, , 140, , i 43, , 146, , 149, , ] 52, , 157, , 161, , 164, , 168, , I70, , 173, , 175, , I77, , 179, , 182, , 184, , 185, , 100, , 120, , 123, , 125, , 128, , 130, , 132, , 133, , 136, , 139, , 141, , 143, , 145, , 146, , 148, , I49, , 151, , 152, , 153, , 154, , 110, , 107, , 109, , 111, , 112, , i 14, , 115, , 116, , 118, , 120, , 121, , 123, , 124, , 125, , 126, , 127, , 128, , 129, , 129, , 130, , 100, , 101, , 101, , 103, , 104, , 105, , 106, , 107, , 107, , 108, , 109, , 109, , 110, , 110, , Ill, , 120, , 95.5, , 96.7, , 97.9, , 98.9, , 130, , 84.6, , 85.5, , 86.3, , 87, , 87.7, , 88.3, , 88.8, , 89.8, , 90.6, , 91.3, , 92.0, , 140, , 75.2, , 75.8, , 76.4, , 76.9, , 77.4, , 77.8, , 78.2, , 78.9, , 79.5, , 80.0, , 80.5, , 80.9, , 150, , 67.0, , 67.4, , 67.9, , 68.2, , 68.6, , 68.9, , 69.2, , 69.7, , 70.2, , 70.6, , 70.9, , 71.2, , 160, , 59.9, , 60.3, , 60.6, , 60.9, , 61.1, , 61.4, , 61.6, , 62.0, , 62.4, , 62.7, , 62.9, , 63.2, , 170, , 53.8, , 54.1, , 54.3, , 54.6, , 54.8, , 55.0, , 55.I, , 55.5, , 55.7, , 56.0, , 56.2, , 56.4, , 180, , 48.6, , 48.8, , 49.0, , 49.2, , 49.3, , 49.5, , 49.6, , 49.9, , 50.1, , 50.3, , 50.5, , 50.6, , 50.8, , 50.9, , 51.0, , 51.2, , 51.3, , 51.5, , 51.6, , 190, , 44.0, , 44.2, , 44.3, , 44.5, , 44.6, , 44.7, , 44.9, , 45.1, , 45.3, , 45.4, , 45.6, , 45.7, , 45.8, , 45.9, , 46.0, , 46.2, , 46.3, , 46.4, , 46.5, , 200, , 40.0, , 40.2, , 40.3, , 40.4, , 40.5, , 40.7, , 40.7, , 40.9, , 41.1, , 41.2, , 41.3, , 41.4, , 41.5, , 41.6, , 41.7, , 41.8, , 41.9, , 42.0, , 42.1, , 210, , 36.6, , 36.7, , 36.8, , 36.9, , 37.0, , 37.1, , 37.2, , 37.3, , 37.4, , 37.6, , 37.7, , 37.8, , 37.8, , 37.9, , 38.0, , 38.1, , 38.2, , 38.3, , 38.3, , 92.5, , 93.5, , 93.9, , 94.4, , 94.9, , 95.3, , 95.7, , 81,3, , 81.6, , 81.9, , 82.3, , 82.6, , 83.0, , 83.2, , 71.5, , 71.8, , 72.0, , 72.3, , 72.6, , 72.9, , 73.1, , 63.4, , 63.6, , 63.8, , 64.0, , 64.3, , 64.5, , 64.6, , 56,6, , 56.7, , 56.9, , 57.1, , 57.3, , 57.4, , 57.6, , 93.0, , 220, , 33.5, , 33.6, , 33.7, , 33.8, , 33.9, , 34.0, , 34.0, , 34.2, , 34.3, , 34.4, , 34.5, , 34.5, , 34.6, , 34.7, , 34.7, , 34.8, , 34.9, , 35.0, , 35.0, , 230, , 30.8, , 30.9, , 31.0, , 31.1, , 31.2, , 31.2, , 31.3, , 31.4, , 31.5, , 31.6, , 31.6, , 31.7, , 31.8, , 31.8, , 31.9, , 31.9, , 32.0, , 32.1, , 32.1, , 240, , 28.5, , 28.5, , 28.6, , 28.7, , 28.7, , 28.8, , 28.8, , 28.9, , 29.0, , 29.1, , 29.1, , 29.2, , 29.3, , 29.3, , 29.4, , 29.4, , 29.5, , 29.5, , 29.6, , 250, , 26.3, , 26.4, , 26.5, , 26.5, , 26.6, , 26.6, , 26.7, , 26.7, , 26.8, , 26.9, , 26.9, , 27.0, , 27.0, , 27.1, , 27.1, , 27.2, , 27.2, , 27.3, , 27.3

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Table 9(b) Design Compressive, , Stress,jC~ (MPa) for Column Buckling, , Class b, , (Clause 7. 1.2.1), Yield Stress, -fY(MPa), , KLJr, , J, 10, , -P, , 200, , 210, , 220, , 230, , 240, , 182, , 191, , 200, , 209, , 218, , 250, 227, , 260, , 280, , 300, , 320, , 340, , 360, , 380, , 4CQ, , 420, , 450, , 480, , 510, , 540, , 236, , 255, , 273, , 291, , 309, , 327, , 345, , 364, , 382, , 409, , 436, , 464, , 491, , 369, , 394, , 419, , 443, , 468, , 20, , 182, , 190, , 199, , 208, , 217, , 225, , 234, , 251, , 268, , 285, , 302, , 319, , 336, , 353, , 30, , 175, , 183, , 192, , 200, , 208, , 216, , 224, , 240, , 256, , 271, , 287, , 302, , 318, , 333, , 348, , 370, , 392, , 414, , 435, , 342, , 360, , 378, , 395, , 40, , 168, , 176, , 183, , 191, , 198, , 206, , 213, , 228, , 242, , 256, , 270, , 283, , 297, , 310, , 323, , 50, , 161, , 167, , 174, , 181, , 188, , 194, , 201, , 214, , 226, , 238, , 250, , 261, , 272, , 283, , 293, , 308, , 322, , 335, , 347, , 226, , 235, , 243, , 251, , 259, , 269, , 279, , 287, , 295, , 181, , 187, , 197, , 207, , 217, , 162, , (66, , 171, , 179, , 187, , 194, , 201, , 207, , 213, , 218, , 223, , 230, , 236, , 241, , 246, , 147, , 150, , 154, , 160, , 165, , 170, , 175, , 179, , 183, , 186, , 190, , 194, , 198, , 201, , 204, , 129, , 131, , 134, , 136, , 141, , 144, , 148, , 151, , 154, , 156, , 159, , 161, , 163, , 166, , 168, , 170, , 114, , 116, , 118, , 120, , 123, , 126, , 128, , 130, , 132, , 134, , 135, , 137, , 139, , 140, , 142, , 143, , 121, 104, , 60, , 152, , 158, , 164, , 170, , 176, , 70, , 142, , 147, , 152, , 157, , 80, , 131, , 135, , 139, , 143, , 90, , 120, , 123, , 126, , IC43, , 108, , 110, , 112, , 110, , 96.5, , 98.3, , 120, , 86.2, , 87.5, , 100, , 88.6, , 101, , 89.7, , 103, , 90.7, , 104, , 91.7, , 105, , 92.5, , 107, , 94.1, , 109, , 95.4, , 96.6, 84.6, , 112, 97.7, , 98.6, , 116, , 117, , 118, , 119, , 100, , 100, , 101, , 102, , 103, , 104, , 87.3, , 88.6, , 89.2, , 89.8, , 90.3, , 78.7, , 79.5, , 80.3, , 81.0, , 81.6, , 82.7, , 140, , 68.7, , 69.4, , 70.1, , 70.7, , 71.3, , 71.8, , 72.3, , 73.1, , 73.9, , 74.6, , 75.2, , 75.7, , 76.2, , 76.6, , 77.1, , 77.6, , 78.1, , 78.5, , 78.9, , 63.6, , 64.0, , 64.3, , 65.0, , 65.6, , 66.1, , 66.6, , 67.0, , 67.4, , 67.7, , 68.1, , 68.5, , 68,9, , 69.2, , 69.5, , 62.1, , 62.6, , 160, , 86.8, , 87.9, , 77.8, , 61.6, , 86.1, , 115, , 76.9, , 63.1, , 85.4, , 114, , 130, 150, , 83.7, , 111, , 121, , 55.4, , 55.8, , 56.2, , 56.6, , 56.9, , 57.3, , 57.5, , 58.1, , 58.5, , 59.0, , 59.3, , 59.7, , 60.0, , 60.3, , 60.5, , 60.9, , 61.2, , 61.5, , 61.7, , 170, , 50.0, , 50.3, , 50.7, , 51.0, , 51.2, , 51.5, , 51.7, , 52.2, , 52.5, , 52.9, , 53.2, , 53.5, , 53.7, , 53.9, , 54.1, , 54.4, , 54.7, , 54.9, , 55.1, , 180, , 45.3, , 45.6, , 45.9, , 46,1, , 46.3, , 46.5, , 46.7, , 47.1, , 47.4, , 47.7, , 47.9, , 48.1, , 48.3, , 48.5, , 48.7, , 48.9, , 49.2, , 49.3, , 49.5, , 190, , 41.2, , 41.5, , 41.7, , 41.9, , 42.I, , 42.2, , 42.4, , 42.7, , 42.9, , 43.2, , 43.4, , 43.6, , 43.7, , 43.9, , 44.0, , 44.2, , 44,4, , 44.6, , 44.7, , 200, , 37.6, , 37.8, , 38.0, , 38.2, , 38.3, , 38.5, , 38.6, , 38.9, , 39.1, , 39.3, , 39.5, , 39.6, , 39.8, , 39.9, , 40.0, , 40.2, , 40.3, , 40.5, , 40.6, , 210, , 34.5, , 34.7, , 34.8, , 35.0, , 35.1, , 35.2, , 35.3, , 35.5, , 35.7, , 35.9, , 36.0, , 36.2, , 36.3, , 36.4, , 36.5, , 36.6, , 36.8, , 36.9, , 37.0, , 220, , 31.7, , 31.9, , 32.0, , 32.1, , 32.2, , 32.3, , 32.4, , 32.6, , 32.8, , 32.9, , 33.0, , 33.1, , 33.2, , 33.3, , 33.4, , 33.6, , 33.7, , 33.8, , 33.9, , 230, , 29.2, , 29.4, , 29.5, , 29.6, , 29.7, , 29.8, , 29.9, , 30.0, , 30.1, , 30.3, , 30.4, , 30.5, , 30.6, , 30.7, , 30.7, , 30.8, , 30.9, , 31.0, , 31.1, , 240, , 27.1, , 27.2, , 27.3, , 27.3, , 27.4, , 27.5, , 27.6, , 27.7, , 27.8, , 27.9, , 28.0, , 28.1, , 28.2, , 28.3, , 28.3, , 28.4, , 28.5, , 28.6, , 28.7, , 250, , 25.1, , 25.2, , 25.3, , 25.3, , 25.4, , 25.5, , 25.6, , 25.7, , 25.8, , 25.9, , 26.0, , 26.0, , 26.1, , 26.2, , 26.2, , 26.3, , 26.4, , 26.5, , 26.5, .., N, , o, 0, , d

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Table 9(c) Design Compressive, , Stress,jC~ (MPa) for Column Buckling, , Class c, , 6, ~, o, .., , (Clause 7.1 .2.1), Yield Stress, ~Y (MPa), , KL.lr, , J, , &., N, , 200, , 210, , 220, , 230, , 240, , 250, , 260, , 280, , 300, , 320, , 340, , 3641, , 380, , 400, , 420, , 450, , 480, , 510, , 540, , 10, , 182, , 191, , 200, , 209, , 218, , 227, , 236, , 255, , 273, , 291, , 309, , 327, , 345, , 364, , 382, , 409, , 436, , 464, , 491, , 20, , 182, , 190, , 199, , 207, , 216, , 224, , 233, , 250, , 266, , 283, , 299, , 316, , 332, , 348, , 364, , 388, , 412, , 435, , 458, , 30, , 172, , 180, , 188, , 196, , 204, , 21 I, , 219, , 234, , 249, , 264, , 278, , 293, , 307, , 321, , 335, , 355, , 376, , 395, , 415, , 40, , 163, , 170, , 177, , 184, , 191, , 198, , 205, , 218, , 231, , 244, , 256, , 268, , 280, , 292, , 304, , 320, , 337, , 352, , 367, , 50, , 153, , 159, , 165, , 172, , 178, , 183, , 189, , 201, , 212, , 222, , 232, , 242, , 252, , 261, , 270, , 282, , 295, , 306, , 317, , 60, , 142, , 148, , 153, , 158, , 163, , 168, , 173, , 182, , 191, , 199, , 207, , 215, , 222, , 228, , 235, , 244, , 252, , 260, , 267, , 70, , 131, , 136, , 140, , 144, , 148, , 152, , 156, , 163, , 170, , 176, , 182, , 187, , 192, , 197, , 202, , 208, , 213, , 218, , 223, , 80, , 120, , 123, , 127, , 130, , 133, , 136, , 139, , 145, , 149, , 154, , 158, , 162, , 165, , 169, , 172, , 176, , 180, , 183, , 186, , 90, , 108, , 111, , 114, , 116, , 119, , 121, , 123, , 127, , 131, , 134, , 137, , 140, , 142, , 144, , 146, , 149, , 152, , 154, , 156, , 100, , 102, , 104, , 105, , 107, , 109, , 112, , 114, , 116, , 119, , 120, , 122, , 124, , 125, , 127, , 129, , 131, , 132, , 100, , 102, , 103, , 104, , 106, , 107, , 108, , 110, , 111, , 112, , 113, , 100, , 97.5, , 110, , 87.3, , 89.0, , 90.5, , 92.0, , 93.3, , 94.6, , 95.7, , 97.9, , 120, , 78.2, , 79.4, , 80.6, , 81.7, , 82.7, , 83.7, , 84.6, , 86.2, , 87.6, , 88.9, , 90.1, , 91.1, , 92.1, , 93.0, , 93.8, , 94.9, , 130, , 70.0, , 71.0, , 71.9, , 72.8, , 73.5, , 74.3, , 75.0, , 76.2, , 77.3, , 78.3, , 79.2, , 80.0, , 80.7, , 81.4, , 82.0, , 82.9, , 140, , 62.9, , 63.6, , 64.4, , 65.0, , 65.6, , 66.2, , 66.7, , 67.7, , 68.6, , 69.3, , 70.0, , 70.7, , 71.2, , 71.8, , 72.3, , 72.9, , 150, , 56.6, , 57.2, , 57.8, , 58.3, , 58.8, , 59.2, , 59.7, , 641.4, , 61.1, , 61.7, , 62.3, , 62.8, , 63.3, , 63.7, , 64.1, , 64.6, , 95.9, , 96.8, , 97.6, , 83.6, , 84.3, , 84.9, , 73.5, , 74.1, , 74.6, , 65.1, , 65.5, , 65.9, , 160, , 51.1, , 51.6, , 52.1, , 52.5, , 52.9, , 53.3, , 53.6, , 54.2, , 54.8, , 55.3, , 55.7, , 56.1, , 56.5, , 56.9, , 57.2, , 57.6, , 58.0, , 58.4, , 58.7, , 170, , 46.4, , 46.8, , 47.1, , 47.5, , 47.8, , 48. I, , 48.4, , 48.9, , 49.3, , 49.8, , 50.1, , 50.5, , 50.8, , 51.1, , 51.3, , 51.7, , 52.0, , 52.3, , 52.6, , 180, , 42.2, , 42.5, , 42.8, , 43.1, , 43.4, , 43.6, , 43.9, , 44.3, , 44.7, , 45.0, , 45.3, , 45.6, , 45.8, , 46.1, , 46.3, , 46.6, , 46.9, , 47.1, , 47.3, , 190, , 38.5, , 38.8, , 39.0, , 39.3, , 39.5, , 39.7, , 39.9, , 40.3, , 40.6, , 40.9, , 41.1, , 41.4, , 41.6, , 41.8, , 42.0, , 42.2, , 42.5, , 42.7, , 42.9, , 200, , 35.3, , 35.5, , 35.7, , 35.9, , 36.I, , 36.3, , 36.5, , 36.8, , 37.0, , 37.3, , 37.5, , 37.7, , 37.9, , 38.1, , 38.2, , 38.4, , 38.6, , 38.8, , 39.0, , 210, , 32.4, , 32.6, , 32.8, , 33.0, , 33.1, , 33.3, , 33.4, , 33.7, , 33.9, , 34.1, , 34.3, , 34.5, , 34.7, , 34.8, , 34.9, , 35.1, , 35.3, , 35.4, , 35.6, , 220, , 29.9, , 30.1, , 30.2, , 30.4, , 30.5, , 30.6, , 30.8, , 31.0, , 31.2, , 31.4, , 31.5, , 31.7, , 31.8, , 31.9, , 32.1, , 32.2, , 32.4, , 32.5, , 32.6, , 230, , 27.6, , 27.8, , 27.9, , 28.0, , 28.2, , 28.3, , 28.4, , 28.6, , 28.8, , 28.9, , 29.1, , 29.2, , 29.3, , 29.4, , 29.5, , 29.7, , 29.8, , 29.9, , 30.0, , 240, , 25.6, , 25.7, , 25.9, , 26.0, , 26.1, , 26.2, , 26.3, , 26.4, , 26.6, , 26.7, , 26.9, , 27.0, , 27.1, , 27.2, , 27.3, , 27.4, , 27.5, , 27.6, , 27.7, , 250, , 23.8, , 23.9, , 24.0, , 24.1, , 24.2, , 24.3, , 24.4, , 24.5, , 24.7, , 24.8, , 24.9, , 25.0, , 25.1, , 25.2, , 25.3, , 25.4, , 25.5, , 25.6, , 25.7

Page 49 :
Table 9(d) Design Compressive, , Stress,~& (MPa) for Column Buckling, , Class d, , (Clause 7.1.2.1), Yield Stress, ~Y (MPa), , KM, , 4, , 200, , 210, , 220, , 230, , 240, , 250, , 260, , 280, , 300, , 320, , 340, , 360, , 380, , 404), , 420, , 450, , 480, , 510, , 540 ‘-, , 10, , 182, , 191, , 200, , 209, , 218, , 227, , 236, , 255, , 273, , 291, , 309, , 327, , 345, , 364, , 382, , 409, , 436, , 464, , 49 I, , 20, , 182, , 190, , 198, , 206, , 215, , 223, , 231, , 247, , 263, , 279, , 294, , 310, , 325, , 340, , 355, , 377, , 399, , 42 I, , 442, , 30, , 168, , 175, , 182, , 189, , i97, , 204, , 211, , 224, , 238, , 25 I, , 264, , 277, , 290, , 302, , 314, , 332, , 350, , 367, , 384, , 40, , 154, , 161, , 167, , 173, , 179, , 185, , 191, , 203, , 214, , 2’25, , 235, , 246, , 256, , 266, , 275, , 289, , 303, , 316, , 328, , 50, , 141, , 147, , 152, , 157, , 162, , 167, , 172, , 182, , 191, , 199, , 208, , 216, , 224, , 231, , 238, , 249, , 258, , 268, , 277, , 60, , 129, , 133, , 137, , 142, , 146, , 150, , 154, , 161, , 168, , 175, , 182, , 188, , 193, , 199, , 204, , 212, , 219, , 225, , 23 I, , 70, , }16, , 120, , 124, , 127, , 130, , 133, , i 37, , 142, , 148, , 153, , 158, , 162, , 167, , 171, , 174, , 180, , 184, , 189, , 193, , 80, , 105, , 108, , 111, , 113, , 116, , 118, , 121, , 125, , 129, , i33, , 137, , 140, , 143, , 146, , 149, , 153, , 156, , 159, , 162, , 101, , 103, , 105, , 107, , 110, , 113, , 116, , 119, , 121, , 123, , 126, , 128, , 130, , 133, , 135, , 137, , 101, , 103, , 105, , 107, , 108, , 110, , 112, , 114, , 116, , 117, , 100, , 10I, , 90, , 94.1, , 100, , 96.4, , 98.6, , 92.6, , 94.0, , 96.7, , 99. I, , 81.0, , 82.1, , 83.2, , 85.3, , 87.1, , 72.1, , 73.0, , 73.9, , 75.5, , 77.0, , 64.5, , 65.2, , 65.9, , 67.2, , 57.2, , 57.8, , 58.4, , 59.0, , 51.6, , 52. !, , .52.6, , 53.1, , 84.3, , 86.2, , 87.9, , 89.6, , 110, , 75.6, , 77.0, , 78.4, , 79.’?, , 120, , 67.8, , 69.0, , 70.1, , 71.1, , 130, , 61.0, , 62.0, , 62.8, , 63.7, , 140, , 55.0, , 55.8, , 56.5, , 150, , 49.8, , 50.4, , 51.0, , 91.1, , 93.1, , 94.4, , 95.5, , 97.1, , 98.5, , 81.7, , 82.6, , 83.5, , 84.7, , 85.8, , 86.9, , 87.8, , 72.1, , 72.8, , 73.5, , 74.5, , 75.4, , 76.2, , 76.9, , 63.3, , 64.0, , 64.6, , 65.2, , 66.0, , 66.7, , 67.3, , 67,9, , 56.6, , 57.2, , 57.7, , 58.1, , 58.8, , 59.3, , 59.9, , 60.4, , 88.8, , 90.4, , 91.8, , 78.3, , 79.5, , 80.6, , 68.3, , 69.4, , 70.4, , 71.2, , 60.0, , 61.0, , 61.8, , 62.6, , 53.9, , 54.7, , 55.4, , 56.0, , 160, , 45.2, , 45.7, , 46.2, , 46.7, , 47,1, , 47.5, , 47.9, , 48.6, , 49.3, , 49.9, , 50.4, , 50.9, , 51.3, , 51.7, , 52.1, , 52.7, , 53.1, , 53.6, , 54.0, , 170, , 41.2, , 41.6, , 42,1, , 42.4, , 42.8, , 43.1, , 43.5, , 44.1, , 44.6, , 45.1, , 45.5, , 45.9, , 46.3, , 46.7, , 47.0, , 47.4, , 47.8, , 48.2, , 48,6, , 180, , 37.7, , 38.0, , 38.4, , 38.7, , 39.0, , 39.3, , 39.6, , 40.1, , 40.5, , 41.0, , 41.3, , 41.7, , 42.0, , 42.3, , 42.6, , 43.0, , 43.3, , 43.6, , 43.9, , 35.4, , 35.7, , 35.9, , 36.2, , 36.6, , 37.0, , 37.4, , 37.7, , 38.0, , 38.2, , 38.5, , 38.7, , 39.1, , 39.4, , 39.6, , 39.9, , 33.6, , 33.9, , 34.2, , 34.5, , 34.7, , 35.0, , 35.2, , 35.4, , 35.7, , 35.9, , 36.2, , 36.4, , 190, , 34.5, , 34.9, , 35.2, , 200, , 31.8, , 32,0, , 32.3, , 32.5, , 32.8, , 33.0, , 33.2, , 210, , 29.3, , 29.6, , 29.8, , 30.0, , 30.2, , 30.4, , 30.5, , 30.9, , 31.2, , 31.4, , 31.7, , 31.9, , 32.1, , 32.3, , 32.5, , 32.7, , 32.9, , 33.1, , 33.3, , 2Z0, , 27.1, , 27.3, , 27.5, , 27.7, , 27.9, , 28.0, , 28.2, , 28.5, , 28.7, , 29.0, , 29.2, , 29.4, , 29.6, , 29.7, , 29.9, , 30.1, , 30.3, , 30.5, , 30.6, , 230, , 25.2, , 25<3, , 25.5, , 25.7, , 25.8, , 26.0, , 26. i, , 26.4, , 26.6, , 26.8, , 27.0, , 27.k, , 27,3, , 27.5, , 27.6, , 27.8, , 27.9, , 28.1, , 28.2, , 240, , 23.4, , 23.6, , 23.7, , 23.9, , 24.0, , 24.i, , 24.2, , 24.5, , 24.7, , 24.8, , 25.0, , 25.2, , 25.3, , 25.4, , 25.5, , 25.7, , 25.9, , 26.0, , 26.1, , 250, , 21.8, , 22.0, , 22. !, , 22.2, , 22.3, , 22.s, , 22.6, , 22.8, , 22.9, , 23.1, , 23.2, , 23.4, , 23.5, , 23.6, , 23.7, , 23.9, , 24.0, , 24.1, , 24.2, , ..

Page 50 :
IS 800:2007, Table 10 Buckling, , Class of Cross-Sections, , (Clause 7.1 .2.2), r, , I, , !, , I, , I, , (1), , Buckling, Class, , Buckling About Axis, , Limits, , Cross-Section, , (2), , k/bf>l.2:, t, <40 mm, , ~lledI-Sections, , (4), , (3), , z-z, Y-Y, , I-Y, , b, c, , z-z, , y-y, , L_u!L-J, , z-z, Y-Y, , b, c, , z-z, y-y, , d, , z-z, .Y-y, , b, c, , z-z, y-v, , c, d, , Hot rolled, , Any, , a, , Cold formed, , Any, , b, , Generally, , Any, , b, , bit,<30, , z-z, , c, , h/t,”<30, , Y-Y, , c, , Any, , c, , Any, , c, , I, ~>l(lomm, , l-y, , I, , d, , ,, r,540 mm, , ~eldedI-Section, , 1<>40mm, , followSection, , ODD, ~elded Box Section, +-Y, , (exceptas below), Thick welds and, , r, “–i–’: ,, , ‘J, , L, , ~z “, , m, , ~, , L, , b, l-y, , -1, , Channel, Angle, T and Solid Sections, , l-y, , Built-upMember, , l-y, , E, , Z7--, , “-3, , I, , i-v, , I, , I, , 44

Page 51 :
IS 800:2007, Table 11 Effective, , Length, , of Prismatic, , Compression, , Members, , (Clause 7.2.2), Boundary Conditions, 7, , At One End, T, Translation, , A, , (1), , Schematic, Representation, , Effective, Length, , At the Other End, \, Rotation, , F, Translation, , \, Rotation, , (2), , (3), , (4), , (6), , (5), $), t\, \I, \, , Restrained, , Restrained, , Free, , Free, /,, , L], , Free, , Restrained, , 2.OL, , Free, , Y, , I, ;, , Restrained, , Free, , Restrained, , /, , 1.OL, , ‘1, , ‘\, , ‘., , Restrained, , Restrained, , Restrained, , Restrained, , A, , Free, , Restrained, , 1.2L, , Restrained, , Free, , 0.8.L, , Restrained, , Restrained, , ,/, L, {, \, \\, , /, , NOTE— L is the unsupportedlength of the compressionmember(see7.2.1)., , 45, , 0.65L

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IS 800:2007, 7.3 Design Details, , (see 9.3.2.2). The ends of compression members faced, for bearing shall invariably be machined to ensure perfect, contact of surfaces in bearing., , 7.3.1 Thickness of Plate Elements, Classification of members on the basis of thickness of, constituent plate elements shall satisfy the widththickness ratio requirements specified in Table 2., , 7.3.4.2 Where such members are not faced for complete, bearing, the splices shall be designed to transmit all, the forces to which the members are subjected., , 7.3.2 Effective Sectional Area, A,, , 7.3.4.3, Wherever, possible,, splices, shall be, proportioned and arranged so that the centroidal axis, of the splice coincides as nearly as possible with the, centroidal axes of the members being jointed, in order, to avoid eccentricity; but where eccentricity is present, in the joint, the resulting stress shall be accounted for., , Except as modified in 3.7.2 (Class 4), the gross, sectional area shall be taken as the effective sectional, area for all compression, members fabricated, by, welding, bolting and riveting so long as the section is, semi-compact or better. Holes not fitted with rivets,, bolts or pins shall be deducted from gross area to, calculate effective sectional area., , 7.4 Column, , 7.3.3 Eccentricity for Stanchions and Columns, , 7.4.1 General, , 7.3.3.1 For the purpose of determining, , Column bases should have sufficient stiffness and, strength to transmit axial force, bending moments and, shear forces at the base of the columns to their, foundation, without exceeding, the load carrying, capacity of the supports. Anchor bolts and shear keys, should be provided, wherever, necessary,, Shear, resistance at the proper contact surface between steel, base and concrete/grout, may be calculated using a, friction coefficient of 0.45., , the stress in a, , stanchion or column section, the beam reactions or, similar loads shall be assumed to be applied at an, eccentricity of 100 mm from the face of the section or, at the centre of bearing whichever dimension gives the, greater eccentricity,, and with the exception of the, following two cases:, a), , b), , In the case of cap connection, the load shall, be assumed to be applied at the face of the, column or stanchion section or at the edge of, packing, if used towards the span of the beam., , Bases, , The nominal bearing pressure between the base plate, and the support below may be determined on the basis, of linearly varying distribution, of pressure. The, maximum bearing pressure should not exceed the, bearing strength equal to 0.6~C~,wheref,~ is the smaller, of characteristic cube strength of concrete or bedding, material., , In the case of a roof truss bearing on a cap,, no eccentricity be taken for simple bearings, without connections capable of developing, any appreciable, moment. In case of web, member, connection, with face, actual, eccentricity is to be considered., , 7.4,1.1 If the size of the base plate is larger than that, required to limit the bearing pressure on the base, support, an equal projection c of the base plate beyond, the Pace of the column and gusset may be taken as, effective in transferring the column load as given in, Fig. 9, such that bearing pressure on the effective area, does not exceed bearing capacity of concrete base., , 7.3.3.2 In continuous columns, the bending moments, due to eccentricities of loading on the columns at any, floor may be divided equally between the columns, above and below that floor level, provided thaL the, moment of inertia of one column section, divided by, its effective length does not exceed 1.5 times the, correspoi~ding value of the other column. Where this, ratio is exceeded, the bending moment shall be divided, in proportion to the moment of inertia of the column, sections divided by their respective effective lengths., , 7.4.2 Gusseted Bases, For stanchion with gusseted bases, the gusset plates,, angle cleats, stiffeners, fastenings, etc, in combination, with the bearing area of the shaft, shall be sufficient to, take the loads, bending moments and reactions to the, base plate without ex~eeding specified strength. All, the bearing surfaces shall be machined to ensure perfect, contact., , 7.3.4 Splices, 7.3.4.1 Where the ends of compression members are, prepared for bearing over the whole area, they shall be, spliced to hold the connected members accurately in, position, and to resist bending or tension, if present. Such, splices should maintain the intended member stiffness, about each axis. Splices should be located as close to, the point of inflection as possible. Otherwise their, capacity should be adequate to carry magnified moment, , 7.4.2.1 Where the ends of the column shaft and the, gusset plates are not faced for complete bearing, the, weldings, fastenings connecting them to the base plate, shall be sufficient to transmit all the forces to which, the base is subjected., , 46

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IS 800:2007, 7.4.2.2 Column and base plate connections, , When only the effective area of the base plate is used, as in 7.4.1.1, C* may be used in the above equation, (see Fig. 9) instead of (a* - 0.3b2)., , Where the end of the column is connected directly to, the base plate by means of full penetration butt welds,, the connection shall be deemed to transmit to the base, all the forces and moments to which the column is, subjected., , 7.4.3.2 When the slab does not distribute the column, load uniformly, due to eccentricity of the load etc,, special calculation shall be made to show that the base, is adequate to resist the moment due to the non-uniform, pressure from below., , 7.4.3 Slab Bases, Columns with slab bases need not be provided with, gussets, but sufficient fastenings shall be provided to, retain the parts securely in place and to resist all, moments and forces, other than direct compression,, including those arising during transit, unloading and, erection,, , 7.4.3.3 Bases for bearing upon concrete, need not be machined on the underside., , 7.4.3,4 In cases where the cap or base is fillet welded, directly to the end of the column without boring and, shouldering, the contact surfaces shall be machined to, give a perfect bearing and the welding shall be, sufficient to transmit the forces as required in 7.4.3., Where full strength butt welds are provided, machining, of contact surfaces is not required., , 7.4.3.1 The minimum thickness, t,, of rectangular slab, bases, supporting columns under axial compression, shall be, t,=, , 2.5w(a2–0.3b2, , )y~0/fY, , > t~, , 7.5 Angle Struts, 7.5.1 Single Angle Struts, , where, w, , The compression in single angles may be transferred, either concentrically to its centroid through end gusset, or eccentrically by connecting one of its legs to a gusset, or adjacent member., , = uniform pressure from below on the slab, base under, the factored, load axial, compression;, , a, b = larger and smaller projection,, , respectively, of the slab base beyond the rectangle, circumscribing the column; and, , tf, , or masonry, , = flange thickness of compression, , 7.5.1.1 Concentric loading, When a single angle is concentrically, loaded in, compression, the design strength may be evaluated, using 7.1.2., , member., , EFFECTIVE PORTION, j, , FIG. 9 EFFECTIVEAREAOF A BASE PLATE, , 47, , STIFFENER

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IS 800:2007, 7.5.1.2 Loaded through one leg, , stress shall not exceed the values based on 7.1.2, The, angles shall be connected together over their lengths, so as to satisfy the requirements of 7.8 and 10.2.5., , The flexura! torsional buckling strength of single angle, loaded in compression through one of its legs may be, evaluated using the equivalent slenderness ratio, ACas, given below:, , 7.5.2.2 Double angle discontinuous struts connected, back-to-back, to one side of a gusset or section by one, or more bolts or rivets in each angle, or by the, equivalent in welding, shall be designed in accordance, with 7.5.1 and the angles shall be connected together, over their lengths so as to satisfy the requirements, of 7.8 and 10.2.5., , where, k,, kz, k3 = constants, condition,, , depending, upon the end, as given in Table 12,, , 7.5.3 Continuous Members, , [-), I, , L,,,,= ~&–, , and k~ =, , Double angle continuous struts such as those forming, the flanges, chords or ties of trusses or trussed girders,, or the legs of towers shall be designed as axially loaded, compression members, and the effective length shall, be taken in accordance with 7.2.4., , (b, +b2)/2t, -, , J, , TCLE, , ‘%, , where, , centre-to-centre, member,, , 1=, , length of the supporting, , 7.5.4 Combined Stresses, In addition to axial loads, if the struts carry loads which, cause transverse bending, the combined bending and, axial stresses shall be checked in accordance with 9.3., For determining the permissible axial and bending, stresses,, the effective, length shall be taken in, accordance with the 7.2 and 8.3., , r=, radius of gyration about the minor axis,, 1’1’, bj, bz = width of the two legs of the angle,, , t=, , thickness, , of the leg, and, , yield stress ratio ( 250~Y)05., , =, , E, , Table 12 Constants, , kl, kz and k~, 7.6 Laced Columns, , St, No., , (1), , of Bolts, at Each End, Connection, No., , (2), , i), , >2, ii), , Gusset/Connetting, Member, Fixity ‘‘, , k,, , k,, , 7.6.1 General, , 7.6.1.1 Members, , (3), , (4), , (5), , (6), , Fixed, , 0.20, , 0.35, , 20, , { 0.70, , 0.60, , 5, , 0.75, , 0.35, , 20, , { 1.25, , 0.50, , 60, , Hinged, Fixed, , 1, , k,, , Hinged, , comprising two main components, laced and tied, should where practicable, have a radius, of gyration about the axis perpendicular to the plane, of lacing not less than the radius of gyration about the, axis parallel to the plane of lacing (see Fig. IOA, and 10 B)., 7.6.1.2 As far as practicable, the lacing system shall, be uniform throughout the length of the column., 7.6.1.3 Except for tie plates as specified in 7.7, double, laced systems (see Fig. 10B) and single laced systems, (see Fig. IOA) on opposite, sides of the main, components shall not be combined with cross members, (ties) perpendicular to the longitudinal axis of the strut, (see Fig. 10C), unless all forces resulting from, deformation of the strut members are calculated and, provided for in the design of lacing and its fastenings., , “ Stiffeners of in-plane rotational restraint provided by the, .gossetkmrmectingmember., For partial restraint, the LCcan be interpolated between the I.C, results for fixed and hinged cases., , 7.5.2 Double Angle Struts, struts,, 7.5.2.1 For double angle discontinuous, connected back to back, on opposite sides of the gusset, or a section, by not less than two bolts or rivets in line, along the angles at each end, or by the equivalent in, welding, the load may be regarded as applied axially., The effective length, KL, in the plane of end gusset, shall be taken as between 0.7 and 0.85 times the, distance between intersections,, depending on the, degree of the restraint provided. The effective length,, KL, in the plane perpendicular to that of the end gusset,, shall be taken as equal to the distance between centres, of intersections. The calculated average compressive, , 7.6.1.4 Single laced systems, on opposite faces of, the components being laced together shall preferably, be in the same direction so that one is the shadow of, the other, instead of being mutually opposed in, direction., 7.6.1.5 The effective slenderness ratio, (KZA-)., of laced, columns shall be taken as 1.05 times the (KVr)o, the, actual maximum slenderness ratio, in order to account, for shear deformation effects., 48

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IS 800:2007, , A, -.., , 1A, . . ---+-+, , ---%fB, , LACING ON, FACE A, , LACING, FACE B, , ---, , ON, , LACING ON, FACE A, , LACING ON, FACE B, , PREFFERED LACING, ARWNGEMENT, , PREFFERED LACING, ARWNGEMENT, , 10B Double Laced System, , 10A Single Laced System, , 10C Double Laced and Single Laced System Combined with Cross Numbers, FIG., , 10 LACED COLUMNS, , 49

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IS 800:2007, , 7.6.2 Width of Lacing Bars, , construction, the effective lengths shall be taken as 0.7, times the distance between the inner ends of welds, connecting the single lacing bars to the members., , In bolted/riveted construction, the minimum width of, lacing bars shall be three times the nominal diameter, of the end boltfrivet., , NOTE — The required section for lacing bars as compression/, tension members shall be determined by using the appropriate, design stresses, ~, subject to the requirements given in 7.6.3,, to 7.6.6 and T~in 6.1., , 7.6.3 Thickness of Lacing Bars, The thickness of flat lacing bars shall not be less than, one-fortieth of its effective length for single lacings, and one-sixtieth of the effective length for double, lacings., , 7.6.7 Attachment to Main Members, The bolting, riveting or welding of lacing bars to the, main members shall be sufficient to transmit the force, calculated in the bars. Where welded lacing bars, overlap the main members, the amoupt of lap measured, along either edge of the lacing bar shall be not less, than four times the thickness of the bar or the thickness, of the element of the members to which it is connected,, whichever is less. The welding should be sufficient to, transmit the load in the bar and shall, in any case, be, provided along each side of the bar for the full length, of lap., , 7.6.3.1 Rolled sections or tubes of equivalent strength, may be permitted instead of flats, for lacings., 7.6.4 Angle of Inclination, Lacing bars, whether in double. or single systems, shall, be inclined at an angle not less than 40° nor more than, 7(P to the axis of the built-up member., 7.6.5 Spacing, , 7.6.5.1 The maximum spacing of lacing bars, whether, connected by bolting, riveting or welding, shall also, be such that the maximum slenderness ratio of the, components, of the main member (al/rl ), between, consecutive lacing connections is not greater than 50, or 0.7 times the most unfavorable, slenderness ratio, of the member as a whole, whichever is less, where al, is the unsupported length of the individual member, between lacing points, and r, is the minimum radius, of gyration of the individual member being laced, together, , 7.6.8 End 7te Plates, Laced compression members shall be provided with, tie plates as per 7.7 at the ends of lacing systems and, at intersection with other members/stays and at points, where the lacing systems are interrupted., 7.7 Battened, 7.7.1 General, , 7.7.1.1 Compression members composed of two main, components, battened should preferably, have the,, individual members of the same cross-section, and, symmetrically disposed about their major axis. Where, practicable, the compression members should have a, radius of gyration about the axis perpendicular to the, plane of the batten not less than the radius of gyration, about the axis parallel to the plane of the batten (see, Fig. 11)., , 7.6.5.2 Where lacing bars are not lapped to form the, connection to the components of the members, they, shall be so connected that there is no appreciable, interruption in the triangulation of the system., 7.6.6 Design of Lacings, 7.6.6.1 The lacing shall be proportioned, transverse shear, Vt, at any point in the, to at least 2.5 percent of the axial force, and shall be divided equally among, lacing systems in parallel planes., , Columns, , to resist a total, member, equal, in the member, all transverse-, , 7.7.1.2 Battened compression members, not complying, with the requirements specified in this section or those, subjected to eccentricity of loading, applied moments, or lateral forces in the plane of the battens (see Fig. 11),, shall be designed according to the exact theory of, elastic stability or empirically, based on verification, by tests., , 7.6.6.2 For members carrying calculated bending stress, due to eccentricity of loading, applied end moments, and/or lateral loading, the lacing shall be proportioned, to resist the actual shear due to bending, in addition to, that specified in 7.6.6.1., , NOTE— If the column section is subjectedto eccentricityor, other moments about an axis perpendicular to battens, the, battens and the column section should be specially designed, for such moments and shears., , 7.6.6.3 The slenderness ratio, KIJr, of the lacing bars, shall not exceed 145. In bolted/riveted construction,, the effective length of lacing bars for the determination, of the design strength shall be taken as the length, between the inner end fastener of the bars for single, lacing, and as 0.7 of this length for double lacings, effectively connected, at intersections., In welded, , 7.7.1.3 The battens shall be placed opposite to each, other at each end of the member and at points where, the member is stayed in its length and as far as, practicable, be spaced and proportioned, uniformly, throughout. The number of battens shall be such that, the member is divided into not less than three bays, 50

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—, , IS 800:2007, within its actual length from centre-to-centre, connections., , Battens shall be of plates, angles, channels, or I-sections, and at their ends shall be riveted, bolted or welded to, the main components so as to resist simultaneously a, shear Vb = VIC/NS along the column axis and a moment, M = V,C12N at each connection,, , of end, , where, , 00;, , 001, 001, 001, , v,, u, I, /, I, I, 1, I, I, I, I, I, I, I, , 01, 10 01, io oi, 100!, , )0, , m, , distance between centre-to-centre, longitudinally;, , N=, , number of parallel planes of battens; and, , s=, , minimum transverse distance between the, centroid of the rivet/bolt group/welding, connecting, the batten, to the main, member., , of battens,, , Tie plates are members provided at the ends of battened, and laced members, and shall be designed by the same, method as battens. In no case shall a tie plate and its, fastenings be incapable of carrying the forces for which, the lacing or batten has been designed., 7.7.2.3 Size, When plates are used for battens, the end battens and, those at points where the member is stayed in its length, shall have an effective depth, longitudinally, not less, than the perpendicular distance between the centroids, of the main members. The intermediate battens shall, have an effective depth of not less than three quarters, of this distance, but in no case shall the effective depth, of any batten be less than twice the width of one, member, in the plane of the battens. The effective depth, of a batten shall be taken as the longitudinal distance, between outermost bolts, rivets or welds at the ends., The thickness of batten or the tie plates shall be not, less than one-fiftieth, of the distance between the, innermost connecting lines of rivets, bolts or welds,, perpendicular to the main member., , .{ir.--yip, _—, ______, ----—----______, Y, , c=, , 7.7.2.2 Tie plates, , 100[, 100, 100’, !00!, , ------1----------------%, d’-+, I, , = transverse shear force as defined above;, , I, , FIG. 11 BATTENCOLUMNSECTION, 7.7.1.4 The effective slenderness ratio (K!A-). of battened, columns, shall be taken as 1.1 times the (ILVr)o, the, maximum actual slenderness ratio of the column, to, account for shear deformation effects., , 7.7.2.4 The requirement of bolt size and thickness of, batten specified above does not apply when angles,, channels or I-sections are used for battens with their legs, or flanges perpendicular to the main member. However,, it should be ensured that the ends of the compression, members are tied to achieve adequate rigidity., , 7.7.2 Design of Battens, , 7.7.2.1 Battens, Battens shall be designed to carry the bending moments, and shear forces arising from transverse shear force V[, equal to 2.5 percent of the total axial force on the whole, compression member, at any point in the length of the, member, divided equally between parallel planes of, battens. Battened member carrying calculated bending, moment due to eccentricity of axial loading, calculated, end moments or lateral loads parallel to the plane of, battens, shall be designed to carry actual shear in, addition to the above shear. The main members shall, also be checked for the same shear force and bending, moments as for the battens., , 7.7.3 Spacing of Battens, In battened compression members where the individual, members are not specifically checked for shear stress, and bending moments, the spacing of battens, centreto-centre of its end fastenings, shall be such that the, slenderness ratio (KZYr) of any component over that, distance shall be neither greater than 50 nor greater, than 0.7 times the slenderness ratio of the member as a, whole about its z-z (axis parallel to the battens)., 51

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IS 800:2007, 7.7.4 Attachment to Main Members, , 7.8.4.1 Compression, members connected by such, riveting, bolting or welding shall not be subjected to, transverse loading in a plane perpendicular, to the, riveted, bolted or welded surfaces., , 7.7.4.1 Welded connections, Where tie or batten plates overlap the main members,, the amount of lap shall be not less than four times the, thickness of the plate. The length of weld connecting, each edge of the batten plate to the member shall, in, aggregate, be not less than half the depth of the batten, plate. At least one-third of the weld shall be placed at, each end of this edge. The length of weld and depth of, batten plate shall be measured along the longitudinal, axis of the main member., , 7.8.5 Where the components are in contact back-toback, the spacing of the rivets, bolts or intermittent, welds shall not exceed the maximum spacing for, compression members given in (see Section 10)., , DESIGN, , In addition, the welding shall be returned along the, other two edges of the plates transversely to the axis, of the main member for a length not less than the, minimum lap specified above., 7.S Compression, Members, Components Back=to=Back, , Composed, , SECTION, 8, OF MEMBERS SUBJECTEDTO, BENDING, , 8.1 General, Members subjected to predominant bending shall have, adequate design strength to resist bending moment,, shear force, and concentrated forces imposed upon and, their combinations, Further, the members shall satisfy, the deflection limitation presented in Section 5, as, serviceability, criteria,, Member subjected to other, forces in addition to bending or biaxial bending shall, be designed in accordance with Section 9., , of Two, , 7.8.1 Compression members composed of two angles,, channels, or tees back-to-back in contact or separated, by a small distance, shall be connected together by, riveting, bolting or welding so that the ratio of most, unfavorable, slenderness of each member between the, intermediate connections is not greater than 40 or 0.6, times the most unfavorable, ratio of slenderness of, the strut as a whole, whichever is less (see Section 10)., , 8.1.1 Effective Span of Beams, The effective span of a beam shall be taken as the, distance between the centre of the supports, except, where the point of application of the reaction is taken, as eccentric at the support, when it shall be permissible, to take the effective span as the length between the, assumed lines of the reactions., , 7.8.2 In no case shall the ends of the strut be connected, together with less than two rivets or bolts or their, equivalent in welding, and there shall be not less than, two additional, connections, in between,, spaced, equidistant along the length of the strut. Where the, members are separated back-to-back, the rivets or bolts, through these connections shall pass through solid, washers or packing in between. Where the legs of the, connected angles or the connected tees are 125 mm, wide or more, or where webs of channels are 150 mm, wide or over, not less than two rivets or bolts shall be, used in each connection, one on line of each gauge, mark., , 8.2 Design Strength, , in Bending, , (Flexure), , The design bending strength of beam, adequately, supported against lateral torsional buckling (laterally, supported beam) is governed by the yield stress, (see 8.2.1). When abeam is not adequately supported, against lateral buckling (laterally un-supported beams), the design bending strength may be governed by lateral, torsional buckling strength (see 8.2.2)., The factored design moment, M at any section, in a, beam due to external actions, shall satisfy, , 7.8,3 Where these connections are made by welding,, solid packing shall be used to effect the jointing unless, the members are sufficiently close together to permit, direct welding, and the members shall be connected, by welding along both pairs of edges of the main, components., , M<M~, where, , M~ = design, , bending strength of the section,, calculated as given in 8.2.1.2., , 7.8.4 The rivets, bolts or welds in these connections, shall be sufficient to carry the shear force and moments,, if any, specified for battened struts (see 7.7.3), and in, no case shall the rivets or bolts be less than 16 mm, diameter for members upto and including 10 mm thick;, 20 mm diameter for members upto and including, 16 mm thick; and 22 mm diameter for members over, 16 mm thick., , 8.2.1 Laterally Supported Beam, A beam may be assumed to be adequately supported, at the supports, provided the compression flange has, full lateral restraint and nominal torsional restraint at, supports supplied by web cleats, partial depth end, plates, fin plates or continuity with the adjacent span., Full lateral restraint to compression flange may be, 52

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IS 800:2007, , M~ = Mdv, , assumed to exist if the frictional or other positive, restraint of a floor connection to the compression flange, of the member is capable of resisting a lateral force, not less than 2.5 percent of the maximum force in the, compression, flange of the member. This may be, considered to be uniformly distributed along the flange,, provided gravity loads constitute the dominant loading, on the member and the floor construction is capable, of resisting this lateral force., , where, , Mdv = design bending strength under high shear as, defined in 9.2., 8.2.1.4 Holes in the tension zone, a), , The design bending strength of a section which is not, susceptible to web buckling under shear before yielding, (where dtw < 67&) shall be determined, according, to 8.2.1.2., , The effect of holes in the tension flange, on, the design bending strength need not be, considered if, @nf, , /Agf), , f~fu, , of partial, safety, factors against ultimate to, yield stress (see 5.4.1)., , When the An~/A~,does not satisfy the above, requirement, the reduced effective flange area,, A#atisfying the above equation maybe taken, as the effective flange area in tension, instead, of A~r, , 8.2.1.2 When the factored design shear force does not, exceed 0.6 V~, where V~is the design shear strength of, the cross-section (see 8.4), the design bending strength,, M~ shall be taken as:, ‘d = &,zpfy, , = ratio of yield and ultimate, stress of the material, and, , Yml/YmO = ratio, , yielding (titW <676), the design bending strength shall, be calculated using one of the following methods:, , The bending moment and axial force acting, on the section maybe assumed to be resisted, by the whole section. In such a case, the web, shall be designed for combined shear and, normal stresses using simple elastic theory in, case of semi-compact webs and simple plastic, theory in the case of compact and plastic, webs., , 4’mo ) / 0.9, , the flange in tension,, , When the flanges are plastic, compact or semi-compact, but the web is susceptible to shear buckling before, , b), , (%,, , Anf /A~~ = ratio of net to gross area of, , before yielding, , The bending moment and axial force acting, on the section maybe assumed to be resisted, by flanges only and the web is designed only, to resist shear (see 8.4)., , W/f.), , where, , 8.2.1.1 Section with webs susceptible to shear buckling, , a), , ~, , b), , The effect of holes in the tension region of, the web on the design flexural strength need, not be considered,, if the limit given in (a), above is satisfied for the complete tension, zone of the cross-section,, comprising, the, tension flange and tension region of the, web., , c), , Fastener holes in the compression zone of the, cross-section need not be considered in design, bending strength calculation,, except for, oversize and slotted holes or holes without, any fastener., , 1 ?(.0, , To avoid irreversible deformation under serviceability, loads, Md shall be less than 1.2 Z. fy /ymo incase of, simply supported and 1.5 Z<Yhy~o in cantilever beams;, , 8.2.1.5, , Shear lag eflects, , The shear lag effects in flanges may be disregarded, provided:, , where, P,, , = 1.0 for plastic and compact sections;, , = Z#ZP for semi-compact sections;, 1%, ZP, Z. = plastic and elastic section modulii of the, cross-section, respectively;, f,, ~mO, , For outstand elements (supported, edge), bOs LO/20; and, , along one, , b), , For internal elements, edges), bis LO/ 10., , along two, , (supported, , where, , = yield stress of the material; and, =, , a), , LO = length, , between points, (inflection) in the span,, , partial safety factor (see 5.4.1)., , of zero moment, , bO = width of the flange with outstand, and, , 8.2.1.3 When the design shear force (factored), V, exceeds 0.6Vd, where V~is the design shear strength of, the cross-section (see 8.4) the design bending strength,, Md shall be taken, , bi, , = width of the flange as an internal element., , Where these limits are exceeded, the effective width, of flange for design strength may be calculated using, 53

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IS 800:2007, specialist literature, or conservatively, satisfying the limit given above., , taken as the value, , corresponding, to elastic lateral buckling, moment (see 8.2.2.1 and Table 14)., , Elastic lateral torsional buckling moment, , 8.2.2 Luterally Unsupported Beams, , 8.2.2.1, , Resistance to lateral torsional buckling need not be, checked separately (member may be treated as laterally, supported, see 8.2.1) in the following cases:, , In case of simply supported, prismatic members with, symmetric cross-section, the elastic lateral buckling, moment, MC, can be determined from:, , a), , Bending is about the minor axis of the section,, , b), , Section is hollow, solid bars, and, , c), , In case of major axis bending, 1~~ (as defined, herein) is less than 0.4., , (rectangular/, , tubular), , or, ‘Cr=m=’bzpfcrb, ~,,b of non-slender, rolled steel sections in the above, equation may be approximately, calculated from the, values given in Table 14, which has been prepared using, the following equation:, , The design bending strength of laterally unsupported, beam as governed by lateral torsional buckling is given, by:, ‘d = ~b ‘pfbd, where, &, , = 1.0 for plastic and compact sections., = Z@P for semi-compact, , sections., , The following simplified equation may be used in the, case of prismatic members made of standard rolled, I-sections and welded doubly symmetric I-sections,, for calculating the elastic lateral buckling moment,, MC,(see Table 14):, , ZP,Z. = plastic section modulus and elastic section, to, extreme, modulus, with respect, compression tibre., fbd, , = design, , bending, compressive, stress,, obtained as given below [see Tables 13(a), and 13(b)], , fbd = XLTfy &O, XLT = bending, , stress reduction factor to, account for lateral torisonal buckling,, given by:, , where, 1,, , = torsional, section;, , constant, , = ~ bi t?/3 for open, , Iw = warping constant;, IY,,rY= moment of inertia and radius of gyration,, respectively, o,’, , = 0.5[l+~L., , cxLT,the imperfection, , parameter, , (~”, , ‘0.2) +A~’2], , /+’, , is given by:, , ., , about, , the weaker axis;, , effective length for lateral torsional buckling, (see 8.3);, , h~ = centre-to-centre distance between flanges; and, , ctL~ = 0.21 for rolled steel section, tf, , =, , thickness, , of the flange., , ~LT = 0.49 fOr welded Steel section, The non-dimensional, by, a LT, , slenderness, , MC, for different beam sections, considering loading,, support condition, and non-symmetric section, shall, be more accurately calculated using the method given, in Annex E., , ratio, k~T, is given, , =V, f,, , 8.3 Effective Length for Lateral, , L, b, , where, , M,, = elastic critical, moment, calculated, accordance with 8.2.2.1, and, ~,. b = extreme, , fibre bending, , compressive, , Torsional, , Buckling, , 8.3.1 For simply supported beams and girders of span, length, 1,, where no lateral restraint to the compression, flanges is provided, but where each end of the beam is, restrained against torsion, the effective length LL~ of, the lateral buckling to be used in 8.2.2.1 shall be taken, as in Table 15., , in, stress, , 54

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Table 13(a) Design Bending, , Compressive, , Stress Corresponding, , to Lateral, , Buckling,, , fM, a~~ = 0.21, , (Clause 8.2.2), , f.r,b, , f,, 200, , 210, , 1000o, , 181.8, , 8000, , 181.8, , 6000, , 181.8, , 190.9, , 409.1, , 436.4, , 463.6, , 490.9, , 409.1, , 436.4, , 463.6, , 490.9, , 381.8, , 409.1, , 436.4, , 463.6, , 490.9, , 436.4, , 463.6, , 490.9, , 420, , 450, , 309.1, , 327.3, , 345.5, , 363,6, , 381.8, , 309.1, , 327.3, , 345,5, , 363.6, , 381.8, , 309.1, , 327.3, , 345.5, , 363.6, , 280, , 300, , 320, , 340, , 200, , 209.1, , 218.2, , 227.3, , 236.4, , 254.5, , 272.7, , 290.9, , 200, , 209.1, , 218.2, , 227.3, , 236.4, , 254.5, , 272.7, , 290.9, , 209.1, , 218.2, , 227.3, , 236.4, , 254.5, , 272.7, , 290.9, , 200, , 540, , 400, , 260, , 190.9, , 510, , 380, , 250, , 190.9, , 480, , 360, , 230, , 240, , 220, , 4000, , 181.8, , 190.9, , 200, , 209.1, , 218.2, , 227.3, , 236.4, , 254.5, , 272.7, , 290.9, , 309.1, , 327.3, , 345.5, , 363.6, , 381.8, , 409.1, , 2000, , 181.8, , 190.9, , 200, , 209.1, , 218.2, , 227.3, , 236.4, , 254.5, , 272.1, , 290.9, , 309.1, , 327.3, , 345.5, , 363.6, , 381.8, , 409. I, , 436.4, , 463.6, , 490.9, , 1000, , 169.1, , 179.5, , 186, , 196.5, , 202.9, , 209.1, , 219.8, , 229.1, , 245.5, , 261.8, , 275.1, , 291.3, , 300.5, , 323.6, , 332.2, , 355.9, , 370.9, , 384.8, , 412.4, , 900, , 169.1, , 179.5, , 186, , 194.5, , 200.7, , 204.5, , 215.1, , 231.6, , 242.7, , 258.9, , 272, , 291.3, , 300.5, , 316.4, , 328.4, , 339.5, , 366.5, , 380.2, , 392.7, 387.8, , 212.7, , 224, , 240, , 258,9, , 268.9, , 284,7, , 293.6, , 301.8, , 324.5, , 335.5, , 349.1, , 370.9, , 202.3, , 208, , 226.5, , 237.3, , 250.2, , 259.6, , 278,2, , 286.7, , 294.5, , 305.5, , 327.3, , 340.4, , 352.4, , 363.3, , 197.7, , 203.3, , 218.9, , 226.4, , 244.4, , 253.5, , 261.8, , 276,4, , 287.3, , 294, , 306.8, , 322.9, , 333.8, , 343.6, , 185.5, , 188.6, , 200.9, , 208.7, , 218.2, , 232.7, , 244.2, , 248.7, , 259.1, , 269.1, , 274.9, , 286.4, , 296.7, , 301.4, , 314.2, , 173.5, , 183.3, , 186.4, , 191.5, , 206.2, , 215.5, , 224, , 231.8, , 242.2, , 248.7, , 258.2, , 263.5, , 274.1, , 279.3, , 292.1, , 294.5, , 169.4, , 174.5, , 184.1, , 186.7, , 196, , 204.5, , 215.3, , 222.5, , 229.1, , 238.4, , 243.6, , 248.2, , 257.7, , 261,8, , 264.3, , 274.9, , 165.2, , 170.2, , 172.7, , 179.6, , 188.4, , 193.6, , 200.7, , 210.2, , 212.7, , 221,1, , 225.5, , 229.1, , 233.2, , 240, , 241.1, , 245.5, , 154.7, , 161.5, , 163.6, , 167.8, , 175.6, , 182.7, , 186.2, , 194.7, , 196.4, , 196.9, , 203.6, , 206.2, , 212.7, , 213.8, , 217.9, , 220.9, , 144.3, , 148.4, , 152.3, , 153.6, , 160.4, , 163.6, , 165.8, , 170, , 173.5, , 179.6, , 178.2, , 179.5, , 184.1, , 183.3, , 185.5, , 191.5, , 134.7, , 137.5, , 141.8, , 142.5, , 145.3, , 147.3, , 148.5, , 149.1, , 152.7, , 151.4, , 152.7, , 153, , 157.1, , 800, , 167.3, , 177.5, , 184, , 190.3, , 196.4, , 206.8, , 700, , 163.6, , 171.8, , 182, , 188.2, , 192, , 600, , 161.8, , 168, , 176, , 181,9, , 194.2, , 500, , 161.8, , 166.1, , 172, , 179.8, , 450, , 158.2, , 164.2, , 168, , 400, , 150.9, , 162.3, , 166, , 350, , 147.3, , 152.7, , 162, , 300, , 143.6, , 147, , 152, , 250, , 134.5, , 137.5, , 142, , 200, , 121.8, , 124.1, , 126, , 129.6, , 130.9, , 134.1, , 150, , 101.8, , 103.1, , 104, , 104.5, , 106.9, , 106.8, , 108.7, , 109.5, , 111.8, , 113.5, , 114.4, , 114.5, , 117.5, , 116.4, , 118.4, , 118.6, , 117.8, , 120.5, , 122.7, , 100, , 74.5, , 76.4, , 76, , 77.4, , 76.4, , 77.3, , 78, , 78.9, , 79.1, , 78.5, , 80.4, , 81.8, , 79.5, , 80, , 80.2, , 81.8, , 82,9, , 83.5, , 83.5, , 90, , 67.3, , 68.7, , 70, , 69, , 69.8, , 70.5, , 70.9, , 71.3, , 70.9, , 72.7, , 74.2, , 72, , 72.5, , 72.7, , 72.5, , 73.6, , 74.2, , 74.2, , 73.6, , 64.9, , 65.5, , 65.6, , 65.5, , 64.9, , 65.5, , 65.5, , 64.9, , 68.7, , 80, , 61.8, , 63, , 62, , 62.7, , 63.3, , 63.6, , 63.8, , 63.6, , 65.5, , 64, , 70, , 54.5, , 55.4, , 56, , 56.5, , 56.7, , 56.8, , 56.7, , 56, , 57.3, , 58.2, , 58.7, , 58.9, , 58.7, , 58.2, , 57.3, , 57.3, , 56.7, , 60.3, , 58.9, , 60, , 47.3, , 47.7, , 48, , 48. I, , 48, , 50, , 49.6, , 48.4, , 49.1, , 49.5, , 49.5, , 49.1, , 48.4, , 50.9, , 49.6, , 49.1, , 52.4, , 51, , 49.1, , 50, , 40, , 40.1, , 40, , 41.8, , 41.5, , 40.9, , 40.2, , 40.7, , 40.9, , 40.7, , 43.3, , 42,5, , 41.5, , 43.6, , 42, , 40.9, , 43.6, , 41.7, , 44.2, , 40, , 32.7, , 32.5, , 32, , 33.5, , 32.7, , 34.1, , 33.1, , 33.1, , 32.7, , 34.9, , 34, , 32,7, , 34.5, , 32.7, , 34.4, , 32.7, , 34.9, , 32.5, , 34.4, , 30, , 25.5, , 24.8, , 26, , 25.1, , 26.2, , 25, , 26, , 25.5, , 24.5, , 26.2, , 24.7, , 26.2, , 24.2, , 25.5, , 26.7, , 24.5, , 26.2, , 27.8, , 24.5, , 20, , 16.4, , 17.2, , 18, , 16.7, , 17.5, , 18.2, , 16.5, , 17.8, , 16.4, , 17.5, , 18.5, , 16.4, , 17.3, , 18.2, , 19.1, , 16.4, , 17.5, , 18.5, , 19.6, , 10, , 9.1, , 9.5, , 8, , 8.4, , 8.7, , 9.1, , 9.5, , 7.6, , 8.2, , 8.7, , 9.3, , 9.8, , 10.4, , 7.3, , 7.6, , 8.2, , 8.7, , 9.3, , 9.8, , G, , m, o, 0, .., N, o, 0, -a, , I

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Table 13(b) Design Bending, , Compressive, , Stress Corresponding, , to Lateral, , Buckling,, , G, , ~~, a~~ = 0.49, , (Clause 8.2.2), I, , 1, f,, , fcr,b, , 200, , m, , 230, , 240, , 250, , 260, , 280, , 300, , 320, , 340, , 360, , 380, , 400, , 420, , 450, , 480, , 510, , 540, , 181.8, , 190.9, , 200.0, , 209.1, , 218.2, , 227.3, , 236.4, , 254.5, , 272.7, , 290.9, , 309.1, , 327.3, , 345.5, , 363.6, , 381.8, , 409.1, , 436.4, , 463.6, , 490.9, , 8000, ., 6000, . ., , 181.8, , 190.9, , 200.0, , 209.1, , 218.2, , 227.3, , 236.4, , 254.5, , 272.7, , 290.9, , 309.1, , 327.3, , 345.5, , 363.6, , 381.8, , 409.1, , 436.4, , 463.6, , 490.9, , 181.8, , 190,9, , 200.0, , 209.1, , 218.2, , 227.3, , 236.4, , 254.5, , 272.7, , 345.5, , 363,6, , 381.8, , 409.1, , 436.4, , 463.6, , 490.9, , 4000, 181.8, ., ., 181.8, 2000, . . .., 160.0, . 1000 ..—., , 190.9, , 200.0, , 209.1, , 218.2, , 227,3, , 236.4, , 254.5, , 272.7, , 290.9, , 309.1, , 327.3, , 345.5, , 363.6, , 381.8, , 409.1, , 436.4, , 463.6, , 490.9, , 190.9, , 200.0, , 209.1, , 218.2, , 227.3, , 236.4, , 254.5, , 272.7, , 290.9, , 309.1, , 327.3, , 345.5, , 363.6, , 381.8, , 409.1, , 436.4, , 463.6, , 490,9, , 247.3, , 255.3, , 266.0, , 280, , 290.2, , 302.7, , 318.5, , 329.2, , 343.6, , 238.0, , 252.0, , 262.5, , 269.1, , 282.5, , 290.5, , 305.5, , 319,9, , 333.8, 319.1, , ., , 290.9, , 309.1, , 327,3, , 164.2, , 170.0, , 179.8, , 185.5, , 190.9, , 196.2, , 211.3, , 220.9, , 235.6, , 164,2, , 170.0, , 173.5, , 183.3, , 188.6, , 193.8, , 203.6, , 218.2, , 226.9, , 171.5, , 176.7, , 181.8, , 191.5, , 201.1, , 210.0, , 224.0, , 234.9, , 242.2, , 252.2, , 258.2, , 271.1, , 282.3, , 296.7, , 306, , 169.4, , 172.4, , 177.3, , 182.0, , 196, , 207.3, , 215.3, , 222.5, , 232.4, , 238.4, , 247.3, , 259.6, , 270, , 279.3, , 292.1, , 304.4, , 168.0, , 172.7, , 177.3, , 188.4, , 193.6, , 203.6, , 213.3, , 222.5, , 228, , 236.4, , 244.4, , 253.6, , 261.8, , 273.5, , 274.9, , 200,9, , 206,2, , 214.2, , 218.2, , 225.3, , 229.1, , 240, , 245.7, , 250,4, , 220.9, , 231.3, , 236.5, , 235.6, , 900, , 154.5, , . 800, 700, , 152.7, , 158.5, , 168.0, , 150.9, , 154.6, , 160.0, , 600, , 145.5, , 150,8, , 154.0, , 161.0, , 500 “’, , 140.0, , 145,1, , 150.0, , 154.7, , 159.3, , 161.4, , 167.8, , 175.6, , 185.5, , 192, , 450, , 134.5, , 141.3, , 144.0, , 148.5, , 152.7, , 156.8, , 160.7, , 168, , 177.3, , 186.2, , 191.6, , 196,4, , 203.8, , 210.9, , 213.8, , 4&”’””, “, , 129.1, , 135.5, , 138.0, , 142.2, , 148.4, , 150, , 153.6, , 162.9, , 169.1, , 174,5, , 182.4, , 183.3, , 193.5, , 196.4, , 202.4, , 208.6, , 209.5, , 217.9, , 220.9, , 350, , 123.6, , 129.8, , 132.0, , 135.9, , 139.6, , 143.2, , 148.9, , 152.7, , 158.2, , 162.9, , 170, , 173.5, , 176.2, , 181.8, , 183.3, , 192.3, , 196.4, , 199.4, , 206.2, , 300, , 118.2, , 122.2, , 126.0, , 129.6, , 130.9, , 134.1, , 137.1, , 142.5, , 147.3, , 154.2, , 157.6, , 157.1, , 162.4, , 167.3, , 168, , 175.9, , 178.9, , 1808, , 181.6, , . 250, ., 200, , 109.1, , 112.6, , 116.0, , 117.1, , 120.0, , 122.7, , 125.3, , 129.8, , 130.9, , 136.7, , 139.1, , 140.7, , 145.1, , 149.1, , 148.9, , 151.4, , 152.7, , 157.6, , 157.1, , 98.2, , 101.2, , 102.0, , 104.5, , 104.7, , 109.1, , 108.7, , 112, , 117.3, , 119.3, , 120.5, , 121.1, , 124.4, , 127.3, , 126, , 130.9, , 130.9, , 129.8, , 132.5, , 150, , 83.6, , 84.0, , 86.0, , 87.8, , 89.5, , 88.6, , 89.8, , 91.6, , 95.5, , 96.0, , 95.8, , 98.2, , 100.2, , 101.8, , 103.1, , 102.3, , 104.7, , 106.6, , 103.1, , 100, , 63.6, , 63.0, , 64.0, , 64.8, , 65.5, , 65.9, , 66.2, , 68.7, , 68.2, , 69.8, , 71.1, , 68.7, , 69.1, , 72.7, , 72.5, , 73.6, , 74.2, , 74.2, , 73.6, , . 90 . ., 80, , 58.2, , 57.3, , 60.0, , 58.5, , 61.1, , 61.4, , 61.5, , 61.1, , 62.7, , 64.0, , 64.9, , 65.5, , 65.6, , 65.5, , 64.9, , 65.5, , 65.5, , 64.9, , 68.7, , 52.7, , 53.5, , 54.0, , 54.4, , 54.5, , 54.5, , 54.4, , 56, , 57.3, , 58.2, , 58.7, , 58.9, , 58.7, , 58.2, , 61.1, , 61.4, , 61.1, , 60.3, , 58.9, , 70, , 47.3, , 47.7, , 48.0, , 48.1, , 48.0, , 50.0, , 49.6, , 50.9, , 49.1, , 49.5, , 52.5, , 52.4, , 51.8, , 50.9, , 53.5, , 53.2, , 52.4, , 55.6, , 54.0, , 60, , 41.8, , 42.0, , 42.0, , 41.8, , 43.6, , 43,2, , 42.5, , 43.3, , 43.6, , 43.6, , 43.3, , 45.8, , 44.9, , 47.3, , 45.8, , 45.0, , 48.0, , 46.4, , 49.1, , 50, , 36.4, , 36.3, , 36.0, , 35.5, , 37.1, , 36.4, , 37.8, , 38.2, , 38.2, , 37.8, , 37.1, , 39.3, , 38.0, , 40.0, , 38.2, , 40.9, , 39.3, , 37.1, , 39.3, , .. 40, .., 30, , 29.1, , 30.5, , 30.0, , 29.3, , 30.5, , 29.5, , 30.7, , 30.5, , 30.0, , 32.0, , 30.9, , 32.7, , 31.1, , 32.7, , 30.5, , 32.7, , 30.5, , 32.5, , 34.4, , 23.6, , 22.9, , 22.0, , 23.0, , 24.0, , 22.7, , 23.6, , 22.9, , 24.5, , 23.3, , 24.7, , 22.9, , 24.2, , 25.5, , 22.9, , 24.5, , 26.2, , 23.2, , 24.5, , 16.4, , I5.3, , 16.0, , 16.7, , I’5.3, , 15.9, , 16.5, , 15.3, , 16.4, , 17.5, , 15.5, , 16.4, , 17.3, , 18.2, , 15.3, , 16.4, , 17.5, , 18.5, , 14.7, , 9. I, , 7.6, , 8.0, , 8.4, , 8.7, , 9.1, , 9.5, , 7.6, , 8.2, , 8.7, , 9.3, , 9.8, , 6.9, , 7.3, , 7.6, , 8.2, , 8.7, , 9.3, , 9.8, , ., , . .20 ., 10, , ., , 220, , 10000, , ., , ‘a, , 210, , 00, =, .., &, s, 4

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Table 14 Critical, , Stress,JC,, b, , JClause 8.2.2.1), 1, , I, , I, ll/tf, , KLlr, , 10, , 8, , 16, , 14, , 18, , 20, , 10, , 22551.2, , 22255.1, , 22092.6, , 21994.1, , 21929.8, , 21885.7, , 20, , 6220.5, , 5947.9, , 5794.5, , 5700.0, , 5637.8, , 5594.7, , 5563.8, , 25, , 30, , I, , ZcI, , 35, , 80, , 60, , 217791o, , I 21763.1, , I 21752.7, , 21740.5, , I 21733.8, , 5515.8, , 5489.7, , 5473.8, , 5463.5, , 5444.8, , —, , 1 21727.2, 5438.2, , —, 1=, , ! 21724.2, , 1, , 30, , 3149.3, , 2905.9, , 2764.6, , 2676.0, , 2616.7, , 2575.3, , 2545.3, , 2498.5, , 2472.8, , 2457.1, , 2447.0, , 2428.3, , 2421.7, , 2418.6, , 40, , 2036.1, , 1821.2, , 1693.0, , I 610.8, , 1555.1, , 1515.8, , 1487.0, , I 441.7, , 1416.5, , 1401.1, , 1391.0, , 1379.0, , 1372.5, , 1365.9, , 1362.8, , 50, , 1492.9, , 1303.2, , I 187,3, , 1111.8, , 1059.9, , 1022.7, , 912.0, , 902.0, , 890.2, , 883.7, , 877.1, , 874.2, , 624.7, , 618.2, , 611.7, , 608.7, , 458.0, , 451.7, , 448.7, , 1 OQ9.5, , 1178.0, , 905.0, , 787.4, , 835.6, , 995.3, , 752.4, , 951.7, , 726.4, , 684.6, , 927.1, 660.9, , 636.4, , 646.1, , I, , 5435.1, , + 5451.4, 2434.9, , 60, , 1, , 12, , 70, , 973.9, , 823.2, , 728.5, , 664.8, , 620.1, , 587.4, , 562.9, , 522.9, , 500.0, , 485.5, , 476.0, , 464.4, , 80, , 831.3, , 695.4, , 609.2, , 550.7, , 509.1, , 478.4, , 455.3, , 417.2, , 395.1, , 381.2, , 371.8, , 360.5, , 354.1, , 347.7, , 344.7, , 90, , 725.9, , 602.6, , 523.6, , 469.5, , 430.9, , 402.2, , 380.4, , 344.2, , 322.9, , 309.3, , 300.2, , 289.1, , 282.8, , 276.5, , 273,5, , 100, , 644.7, , 532.0, , 459.3, , 409,3, , 373.2, , 346.4, , 325.8, , 291.4, , 270.9, , 257.7, , 248.8, , 237.9, , 231.8, , 225.5, , 222.5, , 110, 120, 130, , 580.4, 527.9, 484.3, , 476.6, 431.9, 395.0, , 409.3, 369.5, 3% 9 I,, ““---, , 362.9, 326.0, 7CK1”, ----- T- ,, , 329.2, 294.5, 76:;, 1–, ----,, , 303.9, 270.7, 244-. . ... I,, , 284.5, 252.3, 7767, I,, ----, , 251.8, 221.2, 1971, I,, ----, , 232.1, 202.4, 179o, i1, ----, , 219.3, 190.1, , 210.8, 181.6, , 200.1, 171.2, , 194.0, 165.2, , 187.8, 159.I, , 184,8, 156.2, , 167.1, , 158.8, , 148.6, , 142.8, , 136.7, , 133.9, , 140, , 447.6, , 364.2, , 309.5, , 271.5, , 243.4, , 222.3, , 205.8, , 177.5, , 160.2, , 148.7, , 140.7, , 130.8, , 125.0, , 119.0, , 116.2, , 126.0, , 116.3, , 110.6, , 104.7, , 101.9, , 98.8, , 93.0, , 90.1, , 89.0, 80.7, 73.7, 67.8, 62.6, 58.1, 54.1, 50.6, 47.5, 44.:8 I, , 83.2, 75.0, 68.1, 62.2, 57.1, 52.7, 48.8, 45.4, 42.4, , 80.4, 72.3, , 39.7, , I, , 37.2, , I, , 42.2, , 37.3, , I, , I, , 34.8, , I, I, , 150, , 416.0, , 337.8, , 286.6, , 250.6, , 224.2, , 204.2, , 188.4, , 161.5, , 144.8, , 133.7, , 160, , 388.7, , 315.2, , 266.8, , 232.8, , 207.8, , 188.8, , 173.9, , 148.2, , 132.0, , 121.3, , 113.9, , 104.3, , 170, , 364.9, , 295.4, , 249.6, , 217.5, , 193.7, , 175.6, , 161.4, , 136.7, , 121.3, , 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, , 343.9, 325.2, 308.3, 293.3, 279.5, 267.1, 255.8, 245.3, 235.7, 226.8, , 278.0, 262.6, 248.8, 236.5, 225.3, 215.2, 205.8, 197.3, 189.5, 182.3, , 234.6, 221.3, 209.6, 198.9, 189.3, 180.7, 172.8, 165.6, 159.0, 152.8, , 204.1, 192.3, 181.7, 172.4, 163.9, 156.3, 149.4, 143.0, 137.3, 131.9, , 181.5, 170.7, 161.2, 152.7, 145.1, 138.2, 132.0, 126.3, 121.1, 116.3, , 164.2, 154.2, 145.4, 137.6, 130.6, 124.3, 118.6, 113.4, 108.7, 104.3, , 150.6, 141.2, 133.0, 125.7, 119.1, 113.3, 108.0, 103.2, 98.8, 94.7, , 127.1, 118.6, 111.3, 104.8, 99.0, 93.9, 89.3, 85.1, 81.3, 77...91, , 112.2, 104.3, 97.5, 91.5, 86.2, 81.5, 77.2, 73.5, 70.1, 670, .,. . II, , 111.0, 102.2, 94.6, 88.1, 82.4, 77.4, 72.9, 69.0, 65.5, 62.3, , 103.6, 95.2, 87.8, 81.4, 75.9, 71.2, 66.9, 63.1, 59.7, 56.7, , 94.4, 86.0, 79.0, 72.8, 67.5, 62.9, 58.9, 55.3, 52.1, 49.3, , 126.9, , 111.9, , 100.2, , 91.1, , 74.7, , 122.3, , 107.8, , 118.1, , 104.1, , I, , 280, , 290—, .--- ...—., 300, , I, , 218.6, , I, , 210.9, 203.8, , 1, , I, , 169.4, 163.7, , I, , 147.2, , 175.7, , I, , 141.9, 137.1, , I, , 1, , I, , %.6, 93.2, , I, , 87.7, 84.5, , I, , 71..8, , 64.1, 615, ----, , 69.1, , 59.1, , 594 ., -.., , I, I, , I, , [, , 5A ‘1, ----, , 52.1, , 53.9, , 1, I, , 1, , 49.2, , 47.1, , 46.8, , rt, , 44.4, , 51.5, , 56.8, , 1, , 42.2, , 40.4, , I, , 1, , 40.0, 1, , 38.1, , 36.2, , 65.3, 59.5, 54.5, 50.1, 46.2, 42.8, , 35.2, t, , 33.2, , 31.5, , I, , 39.8, , 32.7, !, , 30.8, , 29.0, , {, , .., ~, o, , -1

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IS 800:2007, Insitnply supported beams with intermediate lateral, restraints against lateral torsional buckling, the effective, length for lateral torsional, buckling, to be used, in 8.2.2.1, ~~ shall be taken as the length of the relevant, segment in between the lateral restraints. The effective, length shall be equal to 1.2 times the length of the, relevant segment in between the lateral restraints., , at that point, relative to the end supports., The, intermediate, lateral restraints, should be either, connected to an appropriate bracing system capable, of transferring the restraint force to the effective lateral, support at the ends of the member, or should be, connected to an independent robust part of the structure, capable of transferring the restraint force. Two or more, parallel member requiring such lateral restraint shall, not be simply connected together assuming mutual, dependence for the lateral restraint., , Restraint against torsional rotation at supports in these, beams may be provided by:, a), , web or flange cleats, or, , b), , bearing stiffeners acting in conjunction, the bearing of the beam, or, , c), , lateral end frames or external, supports, providing lateral restraint to the compression, flanges at the ends, or, , d), , their being built into walls., , The intermediate lateral restraints should be connected, to the member as close to the compression flange as, practicable., Such restraints should be closer to the, shear centre of the compression flange than to the shear, centre of the section. However, if torsional restraint, preventing relative rotation between the two flanges is, provided, the intermediate, lateral restraint may be, connected at any appropriate level., , with, , 8.3.2 For beams, which are provided with members, , For beams which are provided with members giving, effective lateral restraint at intervals along the span,, the effective lateral restraint shall be capable of resisting, a force of 2.5 percent of the maximum force in the, compression flange taken as divided equally between, the points at which the restraint members are provided., Further, each restraint point should be capable of, resisting 1 percent of the maximum force in the, compression flange., , giving effective lateral restraint to the compression, flange at intervals along the span, in addition to the, end torsional restraint required in 8.3.1, the effective, length for Iateral torsional buckIing shall be taken as, the distance, centre-to-centre of the restraint members, in the relevant segment under normal loading condhion, and 1.2 times this distance, where the load is not acting, on the beam at the shear and is acting towards the shear, centre so as to have destabilizing effect during lateral, torsional buckling deformation., , 8.3.4.1 In a series of such beams, with solid webs,, which are connected together by the same system of, restraint members, the sum of the restraining forces, required shall be taken as 2.5 percent of the maximum, flange force in one beam only,, , 8.3.3 For cantilever beams of projecting length L, the, effective length .L~Tto be used in 8.2.2.1 shall be taken, as in Table 16 for different support conditions., 8.3.4 Where a member is provided intermediate lateral, supports to improve the lateral buckling strength, these, restraints should have sufficient strength and stiffness, to prevent lateral movement of the compression flange, Table 15, , Effective, , Length, , 8.3.4.2 In the case of a series of latticed beams, girders, or roof trusses which are connected together by the same, system of restraint members, the sum of the restraining, , for Simply Supported, , Beams, L~T, , (Clause 8.3. 1), SI, , Conditions, , No., , Loading Condition, , of Restraint at Supports, , /, , >, , TorsionalRestraint, , WarpingRestraint, , (2), , (3), , (1), i), ii), iii), , iv), v), , vi), vii), , ~, , Destabilizing, (4), , (5), , Fullyrestrained, , Both flangesfullyrestrained, , Fully restrained, Fully restrained, Fully restrained, Fully restrained, Partially restrained by bottom flange, support connection, Partially restrained by bottom flange, bearing support, , Compression flange fully restrained, Both flanges fully restrained, Compressicmflange partially restrained, Warping not reslrdined in both flanges, Warping not restrained in both flanges, , 0.70 L, 0.75 L, 0.80 L, 0.85 L, 1.00 L, , 0.85 L, 0.90 L, 0.95 L, , 1.0 L+2D, , 1.2L+2D, , Warping not restrained in both flanges, , 1.2 L+2D, , 1.4 L+2D, , NOTES, 1 Torsionalrestraintpreventsrotationaboutthe longitudinalaxis., 2 Warpingrestraintpreventsrotationof the flange in its plane., 3 D is the overall depth of the beam., 58, , 1.00L, 1.20L

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IS 800:2007, , Minor Axis Bending:, , forces required shall be taken as 2.5 percent of the, maximum force in the compression flange plus 1.25, percent of this force for every member of the series other, than the first, up to a maximum total of 7.5 percent., , Hot-Rolled, , or Welded, , — 2b t~, , Rectangular hollow sections of uniform thickness:, Loaded parallel to depth (h), , — A h I (b + h), Loaded parallel to width (b) — A b i (b + h), Circular hollow tubes of uniform thickness — 2 A I n, , 8.3.5 Purlins adequately restrained by sheeting need, not be normally checked for the restraining forces, required by rafters, roof trusses or portal frames that, carry predominately, roof loads provided there is, bracing of adequate stiffness in the plane of rafters or, roof sheeting which is capable of acting as a stressed, skin diaphragm., , —A, , Plates and solid bars, where, , A=, , cross-section, , b=, , overall breadth of tubular section, breadth, of I-section flanges,, , d=, , clear depth of the web between flanges,, , of support to the tension (top) flange in the hogging, moment region on lateral restraint to the compression, flange may be considered as per specialist literature., , h=, , overall depth of the section,, , 8.4 Shear, , NOTE — Fastener holes need not be accounted for in plastic, , 8.3.6 In case of beams with double curvature bending,, adequate direct lateral support to the compression, flange in the hogging moment region maybe provided, as given above for simply supported beam. The effect, , tf, , area,, , = thickness of the flange, and, , tw = thickness of the web., design shear strength calculation provided that:, , The factored design shear force, V, in a beam due to, external actions shaIl satisfy, v<, , If A,ndoes not satisfy the above condition, the effective shear, area may be taken as that satisfying the above limit. Block, shear failure criteria may be verified at the end connections., Section 9 maybe referred to for design strength under combined, high shear and bending., , v,,, , where, V~ = design strength, , 8.4.2 Resistance to Shear Buckling, , = v“ / ymo, where, 7.,0 = partial safetY factor, (see 5.4.1)., , against, , 8.4.2.1 Resistance to shear buckling, as specified, when, , shear failure, , d ~ > 67e for a web without stiffeners, and, / w, , The nominal shear strength of a cross-section, Vn,may, be governed by plastic shear resistance (see 8.4.1) or, strength of the web as governed by shear buckling, (see 8.4.2)., 8.4.1 The nominal plastic shear resistance, shear is given by:, , shall be verified, , > 67E ~, r, , under pure, , for a web with stiffeners, , where, , K, = shear buckling coefficient (see 8.4.2.2), and, , Vn= Vp, & = ~250\, , fy, , where, 8.4.2.2 Shear buckling design methods, The nominal shear strength, Vn,of webs with or without, intermediate stiffeners as governed by buckling may, be evaluated using one of the following methods:, , ‘“Y, Av, , = shear area, and, a), , jYW = yield strength of the web., 8.4.1.1 The shear area may be calculated as given below:, I and channel sections:, , Major Axis Bending:, Hot-Rolled, Welded, , —htW, —dtW, , Simple post-critical method — The simple, post critical method, based on the shear, buckling strength can be used for webs of Isection girders, with or without intermediate, transverse stiffener, provided that the web has, transverse stiffeners at the supports., The, nominal shem strength is given by:, Vn= Vcr, , 59

Page 66 :
IS 800:2007, where, , where, , Vc, = shear force corresponding, , to web, , ‘cb = buckling strength, as obtained from, 8.4.2.2(a), , buckling, = Av~~, , f,, , =, , where, 11 = shear stress corresponding to web, buckling, determined as follows:, 1) when, , =, , ~Ws 0.8, , Tb=&w/h, , [f, , yw ‘-3T;, , +y1’]0”5 -l//, , ~., , 1.5 r~ sin 2$, , ($=, , inclination, , of the tension, , field, , = (), , 2) when 0.8< AWC 1.2, 7,=, , yield strength of the tension field, obtained from, , tan-’~, c, , [1-0.8(AW -0.8)] (~YW/fi), , Wtf = the width of the tension field, given, by:, , d cos~ + (c – SC–SJ sin @, where, Aw = non-dimensional, ratio for shear, given by:, , tCr,e =, , fyw :, , yield stress of the web, , d=, , depth of the web, , web slenderness, buckling stress,, , c, , = spacing of stiffeners in the web, , ‘b = shear stress corresponding, buckling of web 8.4.2.2(a), , Sc, s, = anchorage lengths of tension field, along the compression and tension, flange respectively, obtained from:, , the elastic critical shear stress of the, , K, n’ E, ‘eb=, , 0.5, , 12(1 -/.)[dAw~w~, , s=—, , where, Poisson’s ratio, and, , M,,, —, , M~,= reduced plastic moment capacity of, , provided only at supports, , the respective, flange, plate, (disregarding any edge stiffener), after accounting for the axial force,, Nf in the flange, due to overall, bending and any external axial, force in the cross-section,, and is, calculated as:, , = 4.0 + 5.35 /(c/d)2 for cld <1.0, = 5.35 + 4.0 /(c/d)z for cld 21.0, where c, d are the spacing of, transverse stiffeners and depth of, the web, respectively., , Tension field method — The tension field, method, based on the post-shear buckling, strength,, may be used for webs with, intermediate transverse stiffeners, in addition, to the transverse stiffeners at supports, provided, the panels adjacent to the panel under tension, field action, or the end posts provide anchorage, for the tension fields and if cld 21.0, where c,, d are the spacing of transverse stiffeners and, depth of the web, respectively., , Mfr =0.25b, t,2, ,fyf[], -{ivI/(b,, ~lfyl/ymo)}2], where, bf, t~ = width and thickness of the relevant, flange respectively, fyf = yield stress of the flange, 8.5 Stiffened, , In the tension field method, the nominal shear, resistance, Vn,is given by:, , v“ = Vtf, , rb +0.9w,,, , Web Panels, , 8.5.1 End Panels Design (see Fig. 12), The design of end panels in girders, panel (panel A) is designed using, shall be carried in accordance with, herein. In this case the end panel, , where, J(, =[4, , 1<c, , where, , K, = 5.35 when transverse stiffeners are, , b), , 2, , sin@ fyw tw, [, , P=, , to, , tW~vsin @]< VP, 60, , in which the interior, tension field action, the provisions given, should be designed

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IS 800:2007, using only simple, to 8.4.2.2(a)., , post critical, , method,, , 8.5.3 Anchor Forces, , according, , The resultant longitudinal shear, R,~,and a moment kf,~, from the anchor of tension field forces are evaluated, as given below:, , Additionally, the end panel along with the stiffeners, should be checked as a beam spanning between the, flanges to resist a shear force, R,f and a moment, M,f, due to tension tleld forces as given in 8.5.3. Further,, end stiffener should be capable of resisting the reaction, plus a compressive force due to the moment, equal to, M,j (see Fig. 12)., , where, , (1, , 8.5.2 End Panels Designed Using Tension Field Action, (see Fig. 13 and Fig. 14), , 1/2, , Hq = I.zsvp 1–~, , P, , The design of end panels in girders, which are designed, using tension field action shall be carried out in, accordance with the provisions mentioned herein. In, this case, the end panel (Panel B) shall be designed, according to 8.4.2.2(b)., , d, , = web depth, , If the actual, , factored, , shear, , force,, , Additionally it should be provided with an end post, consisting of a single or double stiffener (see Fig. 13, and Fig. 14), satisfying the following:, , of H~ may be reduced by the ratio, a), , Single s~iflener (see Fig. 13) — The top of, the end post should be rigidly connected to, the flange using full streng~h welds., , Cr, , V,f = the basic, , shear, utilizing tension, 8.4.2.2(b), and, , strength, for the panel, field action as given in, , Vcr = critical shear strength for the panel designed, utilizing tension, in 8.4.2.2(a)., , field, , action, , as given, , 8.5.4 Panels with Openings — Panels with opening of, dimension greater than 10 percent of the minimum, panel dimension should be designed without using, tension field action as given in 8.4.2.2(b). The adjacent, panels should be designed as an end panel as given in, 8.5.1 or 8.5.2, as appropriate., , Doulde sf@er, (see Fig. 14) — The end post, should be checked as abeam spanning between, the flanges of the girder and capable of resisting, a shear force R,~and a moment, Mt~due to the, tension field forces as given in 8.5.3., , ,, , BEARING, STIFFENER — “, , v– L,, v,~_ v, , where, , The end post should be capable of resisting, the reaction plus a moment from the anchor, forces equal to 2/3 M,~ due to tension field, forces, where M,f is obtained from 8.5.3, The, width and thickness of the end post are not, to exceed the width and thickness of the, ilange., b), , V in the panel, , designed using tension field approach is less than the, shear strength, VtFasgiven in 8.4.2.2(b), then the values, , \, , PANEL A, , PANEL B, , d, , :<, , ~1 “, , ,~, , NOTES, 1 Panel A is designed utilizing tension field action as given in 8.4.2.2(b)., 2 Panel II is designed without utilizing tension field action as given in tMWa)., 3 Bearing stiffener is designed for the compressive force due to bearing plus compressive force due to the moment M,, as, given in 8.5.3., , FIG. 12 END PANELDESIGNEDNOTUSINGTENSIONFIELDACTION, fj~

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IS 800:2007, , c, , k-, , 1-, , /, , j, 7, , BEARING, STIFFENERAND, ENO POST, , 1, , I, , PANEL A, , PANEL A, , H, , 7, 1!, , :, , NOTES, 1 Panel A is designed utilizi~g tension field action as given in 8.4.2.2(b)., 2 Panel B is designed utilizing tension field action as given in 8.4,2.2(b)., 3 Bearing stiffener and end post is designed for combinationof compressiveloads due to bearing and a moment equal to 2/3 M,t m, given in 8.5.3., , FIG. 13, , END PANEL DESIGNED USINGTENSIONFIELDACTION(SINGLE STIFFENER), , c, , END POST, i, BEARING, , j, , ,, ~, , T, , A, , STIFFENER, PANEL A, , PANEL A, , d, , ., , r, , 1, , w///I, , NOTES, 1 Panel A is designed utilizing tension field action as given in 8.%2.2(b)., 2 Bearing stiffener is designed for compressive force due to hewing as given in 8.4.2.2(a)., 3 End post is designed for horizontal shear R,, and moment M,, as given in 8.5.3., , FIG. 14 END PANELDESIGNEDUSINGTENSIONFIELDACTION(DOUBLHSTIFFENER), 8.6 Design of Beams and Plate Girders, Webs, , longitudinal, , with Solid, , 1), , 4<200, ., , 8.6.1 Minimum Web Thickness, , &, , lW, , The thickness of the web in a section shall satisfy the, following requirements:, , 2), , 8.6.1.1 Serviceability requirement, , a), , When transverse, , 3), , both longitudinal, , [W, , one longitudinal, b), , to flanges along, , when c < d, 4.s, , 270Ew, , tw, , edges), , < ~ 90E (web connected, , when 0.74 d< c c d, .E < m)&w, rw, , stiffeners are not provided,, , ~ < 200c (web connected, rw, , edges),, , when3d2c2d, , 4), to flanges along, , c), , edge only),, , When only transverse stiffeners are provided, (in webs connected to flanges along both, 63, , when c > 3d, the web shall be considered, as unstiffened,, , When transverse stiffeners and longitudinal, stiffeners at one level only are provided, (0.2 d from compression flange) according, to 8.7.13 (a)

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IS 800:2007, 1), , when 2.U > c 2 ci, , .&r = yield stress, flange., , of compression, , 8.6.2 Sectional Properties, ~), , when 0.74 d<c <d, zs, , 8.6.2.1 The effective sectional area of compression, flanges shall be the gross area with deductions for, excessive width of plates as specified for compression, members ( ree Section 7) and for open holes occurring, in a plane perpendicular to the direction of stress at, the section being considered (see 8.2.1.4)., , 250 F%,, , (u, 3), , d), , when c <0.74, , d, , When a second longitudinal, :it neutral axis is provided), , The effective sectional area of tension flanges shall be, the gross sectional area with deductions for holes as, specified in 8.2.1.4., , stiffener (located, , The effective sectional area for parts in shear shall be, tAen as specified in 8.4.1.1., , d, — 5:400Ew, lW, , 8.6.3 Flanges, 8.6.3.1 In riveted or bolted construction, flange angles, shall form as large a part of the area of the flange as, practicable (preferably not less than one-third) and the, number of flange plates shall be kept to a minimum., , dqrthOf the web,, thickness, , of the web,, , spacing of transverse stiffener, (.s[/[~Fig. 12 :md Fig. 13),, yield stress ratio of web=, , 1n exposed situations, where flange angles are used, at, least onc plate of the top flange shall extend over the, full length of the girder, unless the top edge of the web, is machined flush with the flange angles. Where two, or more flange plates are used, tacking rivets shall be, provided, if necessary to comply with the requirements, of Section 10,, , ., ~“fl ., [--./:fi, , and, yield stress of the web., 8.6.1.2 Compr[’ssion flange buckling requirement, , Each flange plate shall extend beyond its theoretical, cut-off point, and the extension shall contain sufficient, rivets, bolts or welds to develop in the plate, the load, calculated for the bending moment on the girder section, (taken to include the curtailed plate) at the theoretical, cut-off point., , [n order m avoid buckling of the compression flange into, Ihe web, the web thickness shall satisfy the following:, a), , When transverse, , stiffeners are not provided, , b), , When transverse, , stiffeners are provided and, , 1), , whenc>l.5d, , 2), , when c < 1.5d, , The outstand of flange plates, that is the projection, beyond the outer line of connections to flange angles,, channel or joist flanges or in the case of welded, constructions their projection beyond the face of the, web or tongue plate, shall not exceed the values given, in 3.7.2 (see Table 2)., In the case of box girders, the thickness of any plate,, or the aggregate thickness of two or more plates, when, these plates are tacked together to form the flange, shall, satisfy the requirements given in 3.7.2 (see Tldble 2)., , where, , 8.6.3.2, , d, , = depth of the web,, , tw, , = thickness of the web,, , c, , = spacing of transverse stiffenel, (see Fig. 12 and Fig. 13),, , E,, , = yield stress ratio of web=, , Flange splices should preferably, not be located at, points of maximum stress. Where splice plates are, used, their area shall be not less than 5 percent in excess, of the area of the flange element spliced; their centre, of gravity shall coincide, as nearly as possible, with, that of the element spliced. There shall be enough bolts,, rivets or welds on each side of the splice to develop, , r, , 250, —, f’)1, , and, , Flange splices, , 64

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IS 800:2007, augment the strength of the web, they shall be placed, on each side of the web and shall be equal in thickness., The proportion of shear force assumed to be resisted, by these plates shall be limited by the amount of, horizontal shear which they can transmit to the flanges, through their fastenings, and such reinforcing plates, and their fastenings shall be carried up to the points, at which the flange without the additional plates is, adequate., , the 10xI in the element spliced plus 5 percent but in no, case should the strength developed be less than 50, percent of’the effective strength of the material spliced., In welded construction, flange plates shall be joined, by complete penetration butt welds, wherever possible., These butt welds shall develop the full strength of the, plates., 8.6.3.3, , Connection offianges to web, , The flanges of plate girders shall be connected to the, web by sufficient rivets, bolts or welds to transmit the, maximum horizontal shear force resulting from the, bending moment gradient in the girder, combined with, any vertical loads which are directly applied to the, flange. If the web is designed using tension field, method as given in 8.4.2.2 (b), the weld should be able, to transfer the tension freld stress, j’ywacting on the, web,, 8.6.3.4, , Bolted/Riveted, , 8.7 Stiffener, 8.7.1 General, , 8.7.1.1 When the web of a member acting alone (that, is without stiffeners) proves inadequate, stiffeners for, meeting, the following, requirements, should be, provided:, , Webs, , 8.6.4.1 Effective sectional, , b), , Load carrying stiflener — To prevent local, buckling, of, the, web, due, to, concentrated loading (see 8.7.3 and 8.7.5)., , c), , Bearing stl~ener — To prevent local crushing, of the web due to concentrated, loading, (see 8.7.4 and 8.7.6)., , d), , Torsion stiflener — To provide torsional, restraint to beams and girders at supports, (see 8.7.9)., , e), , Diagonal, stiffener, — To provide local, reinforcement, to a web under shear and, bearing (see 8.7.7)., , f), , Tension str’’encr— To transmit tensile forces, applied to a web through a flange (see 8.7.8)., , area of web of plate girder, , The effective cross-sectional area shall be taken as the, full depth of the web plate multiplied by the thickness., , The some stiffeners may perform more than one, function and their design should comply with the, requirements of all the functions for which designed., , ~()’r~ — Where webs are varied in thickness in Lhedepth of, the section by the ase of tongue plates or the like, or where the, pt-opcrrtiunof the web included in the flange area is 25 percent, or more of the overall depth, the above approximation is not, pcnnissib]c and the maximum shear stress shall be computed, on theory,, , 8.7.1.2 O[ltstand of web sti~eners, Unless the outer edge k continuously stiffened, the, outstand f’rom the face of the web should not exceed, , 8.6.4.2 Splice,v in vvebs, , 2ot,,E., , Splices and cutouts for service ducts in the webs should, prefembly not be located at points of maximum shear, force and heavy concentrated loads., , When the outstand of web is between 14tqE and 20tq&,, then the stiffener design should be on the basis of a, core section with an outstand of 14t~&,where tqis the, thickness of the stiffener., , Splices in the webs of the plate girders and rolled, sections shall be designed to resist the shears and, moments at the spliced section (see Annex F)., , 8.7.1.3 St(~~bearing length, , In riveted or bolted construction, splice plates shall be, provided, on each side of the web. In welded, construction, web splices shall preferably be made with, complete penetration butt welds., 8.6.4.3, , intermediate tramverse web st~fener — TO, improve the buckling strength of a slender, web due to shear (see 8.7.2)., , Welded construction, , The gap between the web plates and flange plates shall, be kept to a minimum and for fillet welds shall not, exceed 1 mm at any point before welding., 8.6.4, , a), , construction, , For girders in exposed situations and which do not have, flange plates for their entire length, the top edge of the, web plate shall be flush with or above the angles, and, the bottom edge of the web plate shall be flush with or, set back from the angles., 8.6.3.5, , Where, , additional, , Design, , plates, , are required, , The stiff bearing length of any element b,, is that length, which cannot deform appreciably, in bending., To, determine b], the dispersion of load through a steel bearing, element should be taken as 45” through solid material,, such as bearing plates, flange plates, etc (see Fig. 15)., , to, , 65

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IS 800:2007, 8.7.1.4 Eccentricity, , where, , L= length of the stiffener., , Where a load or reaction is applied eccentric to the, centreline of the web or where the centroid of the, stiffener does not lie on the centreline of the web, the, resulting eccentricity of loading should be accounted, for in the design of the stiffener., , If the load or reaction is applied to the flange by a, compression, member, then unless effective lateral, restraint is provided at that point, the stiffener should, be designed as part of the compression, member, applying the load, and the connection between the, column and beam flange shall be checked for the effects, of the strut action., , 8.7.1.5 Buckling resistance of stiffeners, The buckling resistance F~d should be based on the, design compressive stress fcd (see 7.1.2.1) of a strut, (curve c), the radius of gyration being taken about the, axis parallel to the web. The effective section is the, full area or core area of the stiffener (see 8.7.1.2), together with an effective length of web on each side, of the centreline of the stiffeners, limited to 20 times, the web thickness. The design strength used should be, the minimum value obtained for buckling about the, web or the stiffener., , 8.7.2 Design of Intermediate Transverse Web Stl~eners, 8.7.2.1 General, Intermediate transverse stiffeners may be provided on, one or both sides of the web., 8.7.2.2 Spacing, Spacing of intermediate stiffeners, where provided,, shall comply with 8.6.1 depending on the thickness of, the web., , The effective length for intermediate, transverse, stiffeners used in calculating the buckling resistance,, F~~, should be taken as 0.7 times the length, L of the, stiffener., , 8.7.2.3 Outstand ofstifjleners, The outstand, with 8.7.1.2., , The effective length for load carrying web stiffeners, FXd,, used in calculating, the buckling resistance,, assumes that the flange through which the load or, reaction is applied is effectively restrained against, lateral movement relative to the other flange, and, should be taken as:, a), , KL = 0.7 Lwhen flange is restrained against, rotation in the plane of the stiffener (by other, structural elements)., , b), , KL = L, when flange is not so restrained:, , of the stiffeners, , should, , comply, , 8.7.2.4 Minimum stiffeners, Transverse web stiffeners not subject to external loads, or moments should have a second moment of area, Is, about the centreline of the web, if stiffeners are on both, sides of the web and about the face of the web , if, single stiffener on only one side of the web is used, such that:, , t., , w, , ‘ ‘<, , f, , 45° -&-bq—, ,, ;, \\, I, t, X, ‘\ \\, , L,, , I, , A, , FIG. 15 STIFF BEARING LENGTH, b], 66

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IS 800:2007, , ~ > 1.5d3t;, s, , C2, , where, , d=, , depth of the web;, , 8.7.2.6 Connection of intermediate sti$eners to web, Intermediate, transverse, stiffeners, not subject to, external loading should be connected to the web so as, to withstand a shear between each component of the, stiffener and the web (in kN/mm) of not less than:, , tw = minimum, , required, web thickness, for, spacing using tension field action, as given, in 8.4.2.1; and, , c, , t~/(5b, ), where, , = actual stiffener spacing., , tw = web thickness,, b,, , 8.7.2.5 Buckling check on intermediate transverse web, , stiffeners, , Stiffeners not subject to external loads or moments may, terminate clear of the tension flange and in such a, situation the distance cut short from the line of the weld, should not be more than 4tW., , F, = V- VC,/y.O < F,,, where, resistance, stiffeners,, , v=, , = outstand width of the stiffener, in mm., , For stiffeners subject to external loading, the shear, between the web and the stiffener due to such loading, has to be added to the above value., , Stiffeners not subjected to external loads or moments, should be checked for a stiffener force:, , F~~ = design, , in mm; and, , of the intermediate, 8.7.3 Load Carrying Stiffeners, , factored shear force adjacent to the stiffener,, and, , 8.7.3.1 Web check, Load carrying web stiffeners should be provided where, compressive forces applied through a flange by loads, or reactions exceed the buckling strength, FCdW,of the, unstiffened web, calculated using the following:, , Vcr = shear buckling resistance of the web panel, designed without using tension field action, as given in 8.4.2.2(a)., Stiffeners subject to external loads and moments should, meet the conditions for load carrying web stiffeners, in 8.7.3. In addition they should satisfy the following, interaction expression:, , The effective length of the web for evaluating the, slenderness ratio is calculated as in 8.7.1.5. The area, of cross-section is taken as (b, + n I) tW:, where, b], , = width of stiff bearing, (see 8.7.1.3), and, , on the, , flange, , n, = dispersion of the load through the web at, 45°, to the level of half the depth of the crosssection., , If F~c FX, then (F~– FX) should be taken as zero;, where, , The buckling strength of this web about axis parallel, to the web is calculated as given in 7.1.2.1, using, curve ‘c’., , F~ = stiffener force given above;, F~~ = design resistance, , of an intermediate web, stiffener corresponding to buckling about an, axis parallel to the web (see 8.7.1.5);, , 8.7.4 Bearing Stiffeners, , FX = external load or reaction at the stiffener;, , Bearing stiffeners should be provided for webs where, forces applied through a flange by loads or reactions, exceeding the local capacity of the web at its connection, to the flange, FW, given by:, , FX~ = design, , resistance of, a load carrying, stiffener corresponding, to buckling about, axis parallel to the web (see 8.7.1.5);, , M~ = moment, , on the, stiffener, due, to, eccentrically, applied load and transverse, load, if any; and, , FW= (b, + n~) twf,~ll’~o, where, , Mv~= yield, , moment, capacity of the stiffener, its elastic modulus about its, based on, centroidal axis parallel to the web., , 67, , bl, , = stiff bearing length (see 8.7.1.3),, , rq, , = length obtained, , by dispersion, , through the

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IS 800:2007, 8.7.9 Torsional Stiffeners, , flange to the web junction at a slope of 1 :2.5, to the plane of the flange,, , Where bearing stiffeners are required to provide, torsional restraint at the supports of the beam, they, should meet the following criteria:, , tw = thickness of the web, and, .~W = yield stress of the web., 8.7.5 Design of Load Carrying Stiffeners, 8.7.5.1 Buckling check, , a), , Conditions, , b), , Second moment of area of the stiffener section, about the centreline of the web, 1, should be, such that:, , The external load or reaction, FXon a stiffener should, not exceed the buckling resistance, FX~of the stiffener, as given in 8.7.1.5., , of 8.7.4, and, , 1, 2 o.34a, D3TC’, where, , Where the stiffener also acts as an intermediate stiffener, it should be checked for the effect of combined loads, in accordance with 8.7.2.5., , U,, , = 0.006 for L~~It-ys 50,, = 0.3/( ~~ /rY) for 50< ~~ /rY= 100,, = 30/( L~~/rY )2 for L~~Jry >100,, , 8.7.5.2 Bearing check, Load carrying web stiffeners should also be of sufficient, , D=, , size that the bearing strength of the stiffener, FP,~,given, below is not less than the load transferred, FX, , TC~= maximum, , overall depth of beam at support,, thickness, of, compression flange in the span, under consideration,, , F,,, = A,fy,/ (0.8y~0 ) 2 F,, , KL = laterally, , unsupported, effective, length of the compression flange, of the beam, and, , where, , Fx = external load or reaction,, A~ = area of the stiffener, flange, and, , in contact, , with the, , ‘Y, , radius of gyration of the beam, about the minor axis., , 8.7.10 Connection to Web of Load Carrying and, Bearing Stiffeners, , ~Y~ = yield stress of the stiffener., 8.7.6 Design of Bearing Sti#eners, , Stiffeners, which resist loads or reactions applied, through a flange, should be connected to the web by, sufficient welds or fasteners to transmit a design force, equal to the lesser of:, , Bearing stiffeners should be designed for the applied, load or reaction less the local capacity of the web as, given in 8.7.4. Where the web and the stiffener material, are of different strengths the lesser value should be, assumed to calculate the capacity of the web and the, stiffener. Bearing stiffeners should project nearly as, much as the overhang of the flange through which load, is transferred., 8.7.7 Design of Diagonal, , =, , a), , tension capacity of the stiffene~, , b), , sum of the forces applied at the two ends of, the stiffener when they act in the same, direction or the larger of the forces when they, act in opposite directions., , Stiffeners, , and, , Where the web and the stiffener are of different, strengths, the value for design should be taken as given, in 8.7.6., , Stiffeners, which do not extend right across the web,, should be of such length that the shear stress in the, web due to the design force transmitted by the stiffener, does not exceed the shear strength of the web. In, addition, the capacity of the web beyond the end of, the stiffener should be sufficient to resist the applied, force., , 8.7.8 Design of Tension Sti#eners, , 8.7.11 Connection to Flanges, , Tension stiffeners should be designed to carry the, portion of the applied load or reaction less the capacity, of the web as given in 8.7.4 for bearing stiffeners., , 8.7.11.1 In tension, , Diagonal stiffeners should be designed to carry the, portion of the applied shear and bearing that exceeds, the capacity of the web., , Stiffeners required to resist tension should be connected, to the flange transmitting the load by continuous welds, or non-slip fasteners., , Where the web and the stiffener are of different, strengths, the value for design should be taken as given, in 8.7.6., , 8.7.11.2 In compression, Stiffeners, 68, , required, , to resist, , compression, , should

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-, , ., ..k, , _, , ,,, , IS 800:2007, 8.8.2 Where the concentrated or moving load does not, act directly on top of the web, the local effect shall be, considered in the design of flanges and the diaphragms., , either be fitted against, the loaded, flange, or, connected by continuous welds or non-slip fasteners., The stiffener should be fitted against or connected, both flanges when:, , to, , 8.9 Purlins, , a), , a load is applied directly over a support, or, , b), , it forms the end stiffener of a stiffened web,, or, , c), , it acts as a torsion stiffener., , Where concentrated, loads are applied to hollow, sections consideration should be given to local stresses, and deformations, and the section reinforced, as, necessary., Horizontal, , Stiffeners, , Where horizontal stiffeners are used in addition, vertical stiffeners, they shall be as follows:, a), , b), , to, , One horizontal stiffener shall be placed on the, web at a distance from the compression flange, equal to 1/5 of the distance, from the, compression flange angle, plate or tongue, plate to the neutral axis when the thickness, of the web is less than the limits specified, in 8.6.1. The stiffener shall be designed so, that I, is not less than 4ctW>where 1, and tWare, as defined in 8.7.2.4 and c is the actual, distance between the vertical stiffeners, , 8.10 Bending, , Horizontal, web stiffeners, shall extend, between vertical stiffeners, but need not be, continuous over them; and, , d), , Horizontal stiffeners may be in pairs arranged, on each side of the web, or single located on, one side of the web., , in a Non-principal, , Plane, , 8.10.1 When the flexural deflection of a member is, constrained to a non-principal plane by lateral restraints, preventing lateral deflection, then the force exerted by, the restraints shall be determined, and the principal, axes bending moments acting on the member shall be, calculated from these forces and applied forces, by a, rational analysis., The combined effect of bending, about the principal axes shall satisfy the requirements, of Section 9., , A second horizontal, stiffener, (single or, double) shall be placed at the neutral axis of, the girder when the thickness of the web is, less than the limit specified in 8.6.1. This, stiffener shall be designed so that 1, is not less, than dz tw~ where I, and tw are as defined, in 8.7.2.4 and dz is twice the clear distance, from the compression flange angles, plates or, tongue plates to the neutral axis;, , c), , Rails (Girts), , All purlins shall be designed in accordance with the, requirements for uncased beams as specified in 8.2.1, and 8.2.2, and the limitations of bending stress based, on lateral instability of the compression flange and the, limiting deflection specified under 5.6.1 for the design, of purlins. The maximum bending moment shall not, exceed the values specified in 8.2.1. The calculated, deflections should not exceed those permitted for the, type of roof cladding used as specified in 5.6.1. In, calculating the bending moment, advantage may be, taken of the continuity of the purlin over supports. The, bending about the two axes should be determined, separately, and checked according, to the biaxial, bending requirements specified in Section 9., , 8.7.12 Hollow Sections, , 8.7.13, , and Sheeting, , 8.10.2 When the deflections of a member loaded in a, non-principal plane are unconstrained;, the principal, axes bending moments shall be calculated by a rational, analysis. The combined effect of bending about the, principal, axes shall satisfy the requirements, of, Section 9., , MEMBER, , SECTION 9, SUBJECTED TO COMBINED, FORCES, , 9.1 General, This section governs the design of members subjected, to combined forces, such as shear force and bending,, axial force and bending, or shear force, axial force and, bending., , 8.8 Box Girders, The design and detailing of box girders shall be such, as to give full advantage of its higher load carrying, capacity. Box girder shall be designed in accordance, with specialist, literature., The diaphragms, and, horizontal, stiffeners, should conform, to 8.7.12, and 8.7.13., , 9.2 Combined, , Shear and Bending, , 9.2.1 No reduction in moment capacity of the section is, necessary as long as the cross-section is not subjected, to high shear force (factored value of applied shear force, is less than or equal to 60 percent of the shear strength, of the section as given in 8.4). The moment capacity, may be tiiken as, M~ (see 8.2) without any reduction., , 8.8.1 All diaphragms shall be connected such as to, transfer the resultant shears to the web and flanges., 69, , ‘----&

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IS 800:2007, 9.2.2 When the factored value of the applied shear force, is high (exceeds the limit specified in 9.2.1), the, factored moment of the section should be less than the, moment capacity of the section under higher shear, force, lkf~,, calculated as given below:, , where, MY,M, = factored applied moments about the, minor and major axis of the cross-section,, respectively;, , M~~Y,, Mn~Z= design reduced flexural strength under, a), , Plastic or Compact Section, , combined axial force and the respective, uniaxial, moment, acting alone (see, 9.3.1.2);, , P(%–W,) ~ 1.’2-%f,/Ymo, , M,, = Jf, –, , where, , N=, , p=, , (2v/vd-1)2, , N~ = design strength in tension, Tdas obtained, from 6 or in compression, , M~ = plastic, , design moment of the, whole section disregarding high, shear force effect (see 8.2.1.2), considering web buckling effects, (see 8.2.1.1),, , v=, , M~Y,M~Z = design, , strength under corresponding, moment acting alone (see 8.2);, , A~ = gross area of the cross-section;, , factored applied shear force as, governed by web yielding or web, buckling,, , a,, (X2 = constants as given in Table 17; and, Klo = partial factor of safety in yielding., 9.3.1.2 For plastic and compact sections without bolts, holes, the following approximations may be used for, evaluating Mn~Yand Mn~Z:, , by web yielding or web buckling, (see 8.4.1 or 8.4.2),, , Mfd = plastic design strength of the area, , a), , of the cross-section excluding the, shear area, considering, partial, safety factor ymO,and, , Ze = elastic, , section, whole section., , modulus, , Plates, Mn~= M~(l –n2), , b), , Welded I or H sections, , 2, , of the, , Mn,Y= M,,, , Semi-compact Section, ~dv, , =, , Z, , fvi, , due to yielding, , given by N, = A~.fYlY~O;, , Vd = design shear strength as governed, , b), , factored applied axial force (Tension, T, or Compression, P);, , [( )], , M.~Z= M~Z(1 -n)/(1, , y.,, , 5 MdYwhere n > a, , 1- ~, , –0.5a) SM~Z, , where, 9.3 Combined, , Axial Force and Bending, , Moment, , anda = (A–2bt~)/A, , n = N/N~, Under combined axial force and bending moment, section, strength as governed by material failure and member, strength as governed by buckling failure shall be checked, in accordance with 9.3.1 and 9.3.2 respectively., , c), , <0.5, , For standard I or H sections, for n s 0.2, , M.,, = M,,, , MtiY = 1.56 MdY(l -n)(n +0.6), Mnd,= l.ll MdZ(l–n)SM,Z, For rectangular hollow sections and welded, box sections, for n >0.2, , 9.3.1 Section Strength, d), , 9.3.1.1 Plastic and compact sections, In the design of members subjected to combined axial, force (tension or compression) and bending moment,, the following should be satisfied:, , When the section is symmetric, axes and without bolt holes, Mti, = M~, (1 -n)/(1, , (-4J+(*’h), , about both, , -0.5a,) <MdY, , Mm,,= M,: (1 – n) /(1 – 0.5aW)< M~Z, where, , aW=(A-2bt~)/A, Conservatively, the following equation may also be, used under combined axial force and bending moment:, e), , <0.5, , a, =(A-2htW)/A, <0.5, Circular hollow tubes without bolt holes, Mn~= 1.04M~ (1–n17) <M~, , 70

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....__, , . ,_,, ___, , -, , IS 800:2007, 9.3.1.3, , Semi-compact section, , with respect, fibre; and, , In the absence of high shear force (see 9.2.1), semicompact section design is satisfactory under combined, axial force and bending, if the maximum longitudinal, stress under combined axial force and bending, ~,, satisfies the following criteria:, , without, , holes,, , ~,, , ~<lo, , N, , compression, , v = 0.8, if T and M can vary independently,, or otherwise, = 1.0., 9.3.2.2, , f. ~fy%o, For cross-section, reduces to,, , to extreme, , Bending and axial compression, , Members subjected to combined axial compression and, biaxial bending shall satisfy the following interaction, relationships:, , the above criteria, , :+KY, , ~+mfdy, ‘Mdz, –“, , liy, , where, , C~YMY, —+K~~—, M,,, , z <1.(), MdZ, , C’~YMY, , 0.6 KY—+KZ, , ;+, , M,,, , di, , N~, M~Y,M~z are as defined in 9.3.1.1., , M, , C M, ~<1.(), M~Z, , where, Table 17 Constants, , al and CCz, , C~Y,Cm, = equivalent uniform moment factor as per, Table 18;, , (Clause 9.3.1.1), s], , Section, , al, , CZ2, , (1), , (2), , (3), , (4), , i), ii), iii), , I and channel, Circular tubes, Rectanguku’, tubes, Solid rectangles, , 5n>), 2, 1.661, (1–1.13rr2)< 6, 1.73+ 1.8rr], , 2, 2, 1.66/, (1-1 .13n’)<6, 1.73+ 1.8n3, , P = applied axial compression under factored, load;, , No., , iv), , MY,M,= maximum, , factored applied bending, moments, about y and z-axis of the, member, respectively;, , P~vP~Z=, design strength under axial compression, .. ., as governed by buckling about minor (y), and major (z) axis respectively;, , NOTE.— n =NINA., , MdY,Ma, = design bending strength about y (minor), 9.3.2 Overall Member Strength, , or z (major) axis considering laterally, unsupported length of the cross-section, (see Section 8);, , Members subjected to combined, axial force and, bending moment shall be checked for overall buckling, failure as given in this section., 9.3.2.1, , KY = 1+ (AY– 0.2)nY< 1 + 0.8 nY;, K. = 1 + (AZ– 0.2)nZ< 1+ 0.8 n.; and, , Bending and axial tension, , The reduced effective moment, M.f~, under tension and, bending calculated as given below, should not exceed, the bending strength due to lateral torsional buckling,, M~ (see 8.2.2)., , K~~=, , O.IALTn,, 1- (Cm,, -, , 0.25) 21-, , 0.1 ny, (C.,T-, , 0.25), , where, , nY nZ= ratio of actual applied axial force to the, Me,, = [M– VT Zec/A]s, , M~, , design axial strength for buckling about, the y and z axis, respectively, and, , where, , c mLT, M,T=, , factored applied, respectively:, , moment, , and tension,, , A= area of cross-section;, Zec = elastic section modulus, , of the section, , 71, , =, , equivalent uniform moment factor for, lateral torsional buckling as per Table 18, corresponding, to the actual moment, gradient between lateral supports against, torsional, deformation, in the critical, region under consideration.

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IS 800:2007, , VI, >, VI, , 7, , -$, , &, , Al, , 0, ‘YJ, I, , 0, , —, , Al, , e, 0, , I, , 0, , <, ~, 0, , s, y, u, ‘s, , WI, 0, 0“, +, 0, , cm, , 0, , —, , ‘3, , C$, , 3, ., , 0, 0, +, VI, , m, 0“, , 3, VI, , VI, , 0, , h, , \“,, , —, , 7, , VI, VI, , VI, , 0, , VJ, 3, , —, , ;1, , d, , 0, , L#, 72

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- “------, , IS 800:2007, SECTION 10, CONNECTIONS, , tightened, welding., , 10.1.1 This section deals with the design and detailing, requirements for joints between members. Connection, elements consist of components such as cleats, gusset, plates, brackets, connecting plates and connectors such, as rivets, bolts, pins, and welds. The connections in a, structure shall be designed so as to be consistent with, the assumptions made in the analysis of the structure, and comply with the requirements, specified in this, section. Connections shall be capable of transmitting, the calculated design actions., , 10.2 Location, , a), , Nominal Size of, Fastener, d, , p), , (1), , Standard clearance hole — Except where, , b), , Over size hole — Holes of size larger than the, standard clearance holes, as given in Table, 19 may be used in slip resistant connections, and hold down bolted connections,, only, where specified, provided the over size holes, in the outer Ply is covered by a cover plate of, sufficiently, large size and thickness and, having a hole not larger than the standard, clearance hole (and hardened washer in slip, resistant connections)., , c), , Short and long slots — Slotted holes of size, larger than the standard clearance hole, as, given in Table 19 maybe used in slip resistant, connections, and hold, down, bolted, connections, only where specified, provided, the over size holes in the outer ply is covered, by a cover plate of sufficiently large size and, thickness and having a hole of size not larger, than the standard, clearance, hole (and, hardened washer in slip resistant connection)., , 10.1.5 In general, use of different forms of fasteners, to transfer the same force shall be avoided. However,, when different forms of fmteners are used to carry a, shear load or when welding, and fasteners, are, combined, then one form of fastener shall be normally, designed to carry the total load. Nevertheless, fully, tensioned friction grip bolts may be designed to share, the ioad with welding, provided the bolts are fully, , SI, , Details of Fasteners, , fitted bolts, bolts in low-clearance or oversize, holes are specified, the diameter of standard, clearance holes for fasteners shall be as given, in Table 19., , 10.1.4 The ductility of steel assists the distribution of, forces generated within a joint. Effects of residual, stresses and stresses due to tightening of fasteners and, normal tolerances of fit-up need not therefore be, considered in connection design, provided ductile, behaviour is ensured., , No., , after, , Bolts may be located in standard size, over size, short, slotted or long slotted hole., , 10.1.3 Ease of fabrication and erection should be, considered in Ihe design of connections., Attention, should be paid to clearances, necessary, for field, erection, tolerances, tightening of fasteners, welding, procedures, subsequent inspection, surface treatment, md maintenance., , (Clause, , pretension, , 10.2.1 Clearances for Holes for Fasteners, , connected to the surface, section, the ability of the, the applied forces locally, necessary, local stiffening, , Table 19 Clearances, , necessary, , 10.1.6 The partial safety factor in the evaluation of, design strength of connections shall be taken as given, in Table 5., , 10.1 General, , 10.1.2 Where members are, of a web or the flange of a, web or the flange to transfer, should be checked and where, provided., , to develop, , 10.2.2 Minimum Spacing, The distance between centre of fasteners shall not be, less than 2.5 times the nominal diameter of the fastener., for Fastener, , Holes, , 10.2.1), , Size of the Hole= Nominal Diameter of the Fastener+, , Clearances, , mm, Standard Clearance in, Diameter and Width, of slot, , Cher Size, Clearance in Diameter, , Clearance in the Length of the Slot, , (3), , (4), , (5), , < Short Slot, , Long Slot >, (6), , i), , 12– 14, , 1.0, , 3.0, , 4.0, , 2.5 d, , ii), , 16–22, , 2.0, , 4.0, , 6.0, , 2.5 d, , iii), , 24, , 2.0, , 6.0, , 8.0, , 2.5 d, , iv), , Largerthan 24, , 3.0, , 8.0, , 10.0, , 2.5 d, , 73

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IS 800:2007, 10.2.3 Muxlmum Spacing, , not apply to fasteners interconnecting the components, of back to back tension members. Where the members, are exposed to corrosive influences, the maximum edge, distance shall not exceed 40 mm plus 4t, where t is the, thickness of thinner connected plate., , 10.2.3.1 The distance between the centres of any two, adjacent fasteners shall not exceed 32t or 300 mm,, whichever is less, where tis the thickness of the thinner, plate., , 10.2.5 Tacking Fasteners, , 10.2.3.2 The distance between the centres of two, adjacent fasteners (pitch) in a line lying in the direction, of stress, sh~ll not exceed 16t or 200 mm, whichever, is less, in tension members and 12t or 20() mm,, whichever is less, in compression members; where r is, the thickness of the thinner plate. In the case of, compression members wherein forces are transferred, through butting faces, this distance shall not exceed, 4.5 times the diameter of the fasteners for a distance, equal to 1.5 times the width of the member from the, butting faces., , 10.2.5.1 In case of members, when the maximum distance, adjacent fasteners as specified, tacking fasteners not subjected, be used., , covered under 10.2.4.3,, between centres of two, in 10.2.4.3 is exceeded,, to calculated stress shall, , 10.2.5.2 Tacking fasteners shall have spacing in a line, not exceeding 32 times the thickness of the thinner, outside plate or 300 mm, whichever is less. Where the, plates are exposed to the weather, the spacing in line, shall not exceed 16 times the thickness of the thinner, outside plale or 200 mm, whichever is less. In both, cases, the distance between the lines of fasteners shall, not be greater than the respective pitches., , 10.2.3.3 The distance between the centres of any two, consecutive fasteners in a line adjacent and parallel to, an edge of an outside plate shall not exceed 100 mm, plus 4t or 200 mm, whichever is less, in compression, and tension members; where t is the thickness of the, thinner outside plate., , 10.2.5.3 All the requirements specified in 10.2.5.2 shall, generally apply to compression members, subject to, the stipulations in Section 7 affecting the design and, construction of compression members., , 10.2.3.4 When fasteners are staggered at equal intervals, and the gauge does not exceed 75 mm, the spacing, specified in 10.2.3.2 and 10.2.3.3 between centres of, fasteners may be increased by 50 percent, subject to, the maximum spacing specified in 10.2.3.1., , 10.2.5.4 In tension members (see Section 6) composed, of two flats, angles, channels or tees in contact back to, back or separated back to back by a distance not, exceeding the aggregate thickness of the connected parts,, tacking fasteners with solid distance pieces shall be, provided at a spacing in line not exceeding 1000 mm., , 10.2.4 Edge and End Distances, 10.2.4.1 The edge distance is the distance at right angles, to the direction of stress from the centre of a hole to, the adjacent edge. The end distance is the distance in, the direction of stress from the centre of a hole to the, end of the element., , 10.2.5.5 For compression, members, covered in, Section 7, tack~ng fasteners in a line shall be spaced at, a distance not exceeding 600 mm., 10.2.6 Countersank Heads, , In slotted holes, the edge and end distances should be, measured from the edge or end of the material to the, centre of its end radius or the centre line of the slot,, whichever is smaller. In oversize holes, the edge and, end distances should be taken as the distance from the, relevant edge/end plus half the diameter of the standard, clearance hole corresponding to the fastener, less the, nominal diameter of the oversize hole., , For countersunk heads, one-half of the depth of the, countersinking, shall be neglected in calculating the, length of the fastener in bearing in accordance, with 10.3.3., For fasteners, in tension, having, countersunk heads, the tensile strength shall be reduced, by 33.3 percent. No reduction is required to be made, in shear strength calculations., 10.3 Bewing, , 10.2.4.2 The minimum edge and end distances from, the centre of any hole to the nearest edge of a plate, shall not be less than 1.7 times the hole diameter in, case of sheared or hand-flame cut edges; and 1.5 times, the hole diameter in case of rolled, machine-flame cut,, sawn and planed edges., , Type Bolts, , 10.3.1 Effective Areas of Bolts, 10.3.1.1 Since threads can occur in the shear plane,, the area .4Cfor resisting shear should normally be taken, as the net tensile stress area, An of the bolts. For bolts, where the net tensile stress area is not defined, An shall, be taken as the area at the root of the threads., , 10.2.4.3 The maximum edge distance to the nearest, line of fasteners from an edge of any un-stiffened part, should not exceed 12 tE, where c = (250/’)”2 and t is, the thickness of the thinner outer plate. This would, , 10.3.1.2 Where it can be shown that the threads do not, occur in the shear plane, A~ may be taken as the cross, section area, A, at the shank., 74

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IS 800:2007, 10.3.1.3 In the calculation of thread length, allowance, should be made for tolerance and thread run off., , the connected plates) exceeds 5 times the diameter, d, of the bolts, the design shear capacity shall be reduced, by a factor ~1~,given by:, , 10.3.2 A bolt subjected to a factored shear force ( VJ, shall satisfy the condition, , ~,, = 8 d /(3 d+ 1,) = 8 /(3+1,/d), ~i, shall not be more than f$j given in 10.3.3.1. The, grip length, 1~shall in no case be greater than 8d., , v... = Vdb, where V~~is the design strength of the bolt taken as the, smaller of the value as governed, by shear, V~,~, (see 10.3.3) and bearing, V,P~(see 10.3.4)., , 10.3.3.3 Packing plates, The design shear capacity of bolts carrying shear, through a packing plate in excess of 6 mm shall be, decreased by a factor, ~P~given by:, , 10.3.3 Shear Capacity of Bolt, The design strength of the bolt, V~,~as governed shear, strength is given by:, v dstr, , =, , ‘nsb, , ~,, =(1 -0.0125, , tpk), , where, , 1 ~mb, , where, , tP~ = thickness of the thicker packing, in mm., Vn,b = nominal, shear capacity, calculated as follows:, v],, =@, , %)+%, , 10.3.4 Bearing Capacity of the Bolt, , of a bolt,, , The design bearing strength of a bolt on any plate, V~P~, as governed by bearing is given by:, , ‘%,), where, , where, ~, , v npb, , = uitimate tensile strength of a bolt;, , nominal bearing strength of a bolt, , = 2.5 k~d tfu, , nn = number, , of shear planes with threads, intercepting the shear plane;, , where, , n, = number of shear planes without threads, intercepting, , =, , e, , the shear plane;, , ‘b ‘s ‘mailer ‘f ~’, , P, —–0.25,, , 3d0, , A,b = nominal plain shank area of the bolt; and, , dO = diameter of the hole;, , 10.3.3.1 L.ongjoints, , fub,it, , When the length of the joint, lj of a splice or end, connection, in a compression, or tension element, containing more than two bolts (that is the distmce, between the first and last rows of bolts in the joint,, measured in the direction of the load tmnsfer) exceeds, 15a!in the direction of load, the nominal shear capacity, (see 10.3.2), V~~shall be reduced by the factor ~lj, given, by:, =, , 1.075-1,, =, , 1.075-, , /(200, , ~), , but, , 1.0;, u, , e, p = end and pitch distances of the fastener, along bearing direction;, , Anb = net shear area of the bolt at threads, may, be taken as the area corresponding, to, root diameter at the thread., , Plj, , $,, , = Ultimate tensile stress of the bolt and the, ultimate tensile stress of the plate,, respectively;, , d = nominal diameter of the bolt; and, [ = summation of the thicknesses, of the, connected plates experiencing bearing, stress in the same direction, or if the bolts, are countersunk,, the thickness of the, plate minus one half of the depth of, countersinking., , 075<Pli<10, , The bearing resistance (in the direction normal to the, slots in slotted holes) of bolts in holes other than, standard, clearance, holes may be reduced, by, multiplying the bearing resistance obtained as above,, V~p~,by the factors given below:, , o.oo5(lj /d), , where, d = Nominal diameter of the fastener., NOTE—This provisiondoes not apply when the distribution, of shear over the length of joint is uniform, as in the connection, of web of a section to the flanges., , 10.3.3.2 Large grip lengths, , a), , Over size and short slotted holes – 0.7, and, , b), , Long slotted holes, , – 0.5., , NOTE — The block shear of the edge distance due to, bearing force may be checked as given in 6.4., , When the grip length, 1~(equal to the total thickness of, 75

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IS 800:2007, 0 be limited, a bolt subjected only to a factored design, jhe~ force, V,~in the interface of connections at which, $Iip cannot be tolerated, shall satisfy the following:, , 10.3.5 Tension Capacity, Aboltsubjected, satisfy:, , toafactored, , tensile force, Th shall, , V,f < Vd,f, , Th < T~h, where, , where, , Vd,f = Vn,f/ ymf, T~b ‘Tnb\)’mb, T,,~ = nominal tensile, calculated as:, , capacity, , f).90~u~ A,, < fYb ASb (~mb, , Vn,~ = nominal shear capacity of a bolt as, governed, by slip for friction, type, connection, calculated as follows:, , of the bolt,, , f %()), , v~,f = t%n. Kh F., , where, , where, &, , = ultimate tensile stress of the bolt,, Pf, , =, , ~,b = yield stress of the bolt,, A., , = net tensile stress area as specified in the, appropriate Indian Standard (for bolts, where the tensile stress area is not, defined, A,, shall be taken as the area at, the bottom of the threads), and, , to Combined, , frictional resistance, , hoIes,, , = 0.85 for fasteners in oversized and short, slotted holes and for fasteners in long, slotted holes loaded perpendicular to the, slot,, , Sheat- and Tension, , = 0.7 for fasteners in long slotted holes, loaded parallel to the slot,, y~~ = 1.10 (if slip resistance, service load),, , is designed, , at, , = 1.25 (if slip resistance, ultimate load),, , is designed, , at, , F. = minimum, where, , installation, , bolt tension (proof load) at, and may be taken as, , A.bfO>, , factored shear force acting on the bolt,, A nh, , design shear capacity (see 10.3.2),, , =, , net area of the bolt at threads, and, , fO = proof stress (= 0.70~ub)., , Tb = factored tensile force acting on the bolt, and, T~b ., , to s~ip,, , K~ = 1.0 for fasteners in clearance, , A bolt required to resist both design shear force (V,~), and design tensile force (TJ at the same time shall, satisfy:, , V,b =, vdb =, , as, , ne = number of effective interfaces offering, , A,~ = shank area of the bolt., 10.3.6 Bolt Subjected, , coefficient of friction (slip factor), specified in Table 20 @~= 0.55),, , NOTE — Vn.may be, , design tension capacity (see 10.3.5)., , evaluated at, , a service load or ultimate, , load using appropriatepartial safety factors, depending upon, , 10.4 Friction, , whether slip resistance is required at service load or ultimate, load., , Grip Type Bolting, , 10.4.1 In friction grip type bolting, initial pretension, in bolt (usually high strength) develops clamping force, at the interfaces of elements being joined. The frictional, resistance to slip between the plate surfaces subjected, to clamping force opposes slip due to externally applied, shear. Friction grip type bolts and nuts shall conform, to IS 3757. Their installation procedures shall conform, to IS 4000., , 10.4.3.1 Long joints, The provision for the long joints in 10.3.3.1 shall apply, to friction grip connections also., 10.4.4 Capacity after slipping, When friction type bolts are designed not to slip only, under service loads, the design capacity at ultimate load, may be calculated as per bearing type connection, (see 10.3.2 and 10.3.3)., , 10.4.2 Where slip between bolted plates cannot be, tolerated at working loads (slip critical connections),, the requirements of 10.4.3 shall be satisfied. However,, at ultimate loads, the requirements of 10.4.4 shall be, satisfied by all connections., , NOTE — The block shear resistance of the edge distance due, to bearing force may be checked as given in 6.4., , 10.4.5 Tension Resistance, , 10.4.3 Slip Resistance, , A friction bolt subjected to a factored tension force (Tf ), shall satisfy:, , Design for friction type bolting in which slip is required, 76

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IS 800:2007, Tf < Tdf, , where, V,f = applied factored shear at design load,, , where, , V~f = design shear strength,, , Tdf = Tnf1 k, Tn~ = nominal tensile strength of the friction bolt,, calculated, , T~ = externally, , applied, design load, and, , as:, , where, , = net tensile stress area as specified in, various parts of IS 1367 (for bolts where, the tensile stress area is not defined, A., shall be taken as the area at the root of, the threads);, , f2=$[Te-fiqf0bet4], 271, 1;, e, where, , A,, = shank area of the bolt; and, y~~ = partial factor of safety., Average Values for Coefficient, of Friction (pf), (Clause, SI, (1), O, , ii), iii), iv), , v), vi), vii), , viii), , ix), , x), xi), xii), , 1,, , = distance from the bolt centreline to the toe, of the fillet weld or to half the root radius, for a rolled section,, , le, , = distance, , between prying force and bolt, the, minimum, and, is, centreline, of either the end distance or the value given, by:, , 10.4.3), , Treatment of Surface, , Coefficient, of Friction,, , (2), , &, , No., , Surfacesnot treated, Surfacesblastedwith short or grit with, any looserust removed,no pitting, Surfacesblastedwith shot or grit and, hot-dipgalvanized, Surfaces blasted with shot or grit and, spray+netallizedwith zinc (thickness, 50-70 jan), Surfacesblastedwith shot or grit and, paintedwith ethylzincsilicatecoat, (thickness30-60 ~), Sandblastedsurface,atter light rusting, Surfacesblasted with shot or grit and, painted with ethylzinc silicate coat, (thickness60-80 W), Surfacesblasted with shot or grit and, painted with alcalizinc silicate coat, (thickness60-80 ,mn), Surface blasted with shot or grit and, spray metallized with aluminium, (thickness>50 ,mrr), Clean mill scale, Sand blasted surface, Red lead painted surface, , at, , 10.4.7 Where prying force, Q as illustrated in Fig. 16, is significant, it shall be calculated as given below and, added to the tension in the bolt., , f“, = ultimate tensile stress of the bolt;, , Table 20 ~pical, , tension, , T~~ = design tension strength., , 0.9$U~An ~~YbA,b(y~ll %), , A., , factored, , 0.20, 0.50, where, , 0.10, , 2 for non pre-tensioned, tensioned bolt,, , P=, , 0.25, 0.30, 0.52, 0.30, , bolt and 1 for pre-, , ~, , = 1.5,, , b,, , = effective width of flange per pair of bolts,, , f., t, , = proof stress in consistent units, and, = thickness of the end plate., 2Te, , 0.30, , t, , 0.50, , II, , 0.33, 0.48, 0.1, , 10.4.6 Combined Shear and Tension, , B, , Bolts in a connection for which slip in the serviceability, limit state shall be limited, which are subjected to a, tension force, T and shear force, V, shall satisfy:, , I, , TC+Q, , FIG. 16 COMBINEDPRYINGFORCEANDTENSION, 77

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IS 800:2007, , 10.5 Welds and Welding, , shall not be less than 3 mm and shall generally not exceed, 0.7?, or 1.Ot under special circumstances, where t is the, thickness of the thinner plate of elements being welded., , 10.5.1 General, Requirements of welds and welding shall conform to, IS 816 and IS 9595, as appropriate., 10.5.1.1 End, , Table 21 Minimum Size of First Rtm or of a, Single Run Fillet Weld, , returns, , (Clause 10.5.2.3), Fillet welds terminating at the ends or sides of parts, should be returned continuously around the corners, for a distance of not less than twice the size of the, weld, unless it is impractical, to do so. This is, particularly important on the tension end of parts, carrying bending loads., , Thickness of Thicker Part, , Minimum Size, , mm, —_, , mm, , /. —_. —, Over, (1), i), ii), , 10.5.1.2 Lap joint, In the case of lap joints, the minimum lap should not, be less than four times the thickness of the thinner part, joined or 40 mm, whichever is more. Single end fillet, should be used only when lapped parts are restrained, from openings. When end of an element is connected, only by parallel longitudinal fillet welds, the length of, the weld along either edge should not be less than the, transverse spacing between longitudinal welds., , (2), –, , iii), , 10, 20, , iv), , 32, , Up to and, trrcluding, (3), , 10, 20, 32, 50, , (4), 3, , 5, 6, 8 of first run, 10 for minimum size of, weld, , NOTES, 1 When the minimum size of the fillet weld given in the table, is greater than the thickness of the thhner part, the minimum, size of the weld should be equal to the thickness of the thinner, part. The thicker part shall be adequately preheated to prevent, cracking of the weld., 2 Where the thicker part is more than 50 mm thick, special, precautions like pre-heating should be taken., , 10.5.1.3 A single fillet weld should not be subjected to, moment about the longitudinal axis of the weld., , 10.5.3.2 For the purpose of stress calculation in fillet, welds joining faces inclined to each other, the effective, throat thickness shall be taken as K times the fillet size,, upon the angle, where K is a constant, depending, between fusion faces, as given in Table 22., , 10.5.2 Size of Weld, 10.5.2.1 The size of normal fillets shall be taken as the, minimum weld leg size. For deep penetration welds,, where the depth of penetration beyond the root run is, a minimum of 2.4 mm, the size of the fillet should be, taken as the minimum leg size plus 2.4 mm., , 10.5.3.3 The effective throat thickness of a complete, penetration butt weld shall be taken as the thickness of, the thinner part joined, and that of an incomplete, penetration butt weld shall be taken as the minimum, thickness of the weld metal common to the parts joined,, excluding reinforcements., , 10.5.2.2 For fillet welds made by semi-automatic or, automatic processes, where the depth of penetration is, considerably in excess of 2.4 mm, the size shall be, taken considering actual depth of penetration subject, to agreement between the purchaser and the contractor., 10.5.2.3 The size of, 3 mm. The minimum, run fillet weld shall, the risk of cracking, , SI, No., , 10.5.4 Effective Length’or Area of Weld, , fillet welds shall not be less than, size of the first run or of a single, be as given in Table 21, to avoid, in the absence of preheating., , 10.5.4.1 The effective length of fiilet weld shall be, taken as only that length which is of the specified size, and required throat thickness, In practice the actual, length of weld is made of the effective length shown, in drawing plus two times the weld size, but not less, than four times the size of the weld., , 10.5.2.4 The size of butt weld shall be specified by the, effective throat thickness., , 10.5.4.2 The effective length of butt weld shall be taken, as the length of the continuous ftdl size weld, but not, less than four times the size of the weld., , 10.5.3 Effective Throat Thickness, 10.5.3.1 The effective throat thickness of a fillet weld, Table 22 Values of K for Different, , Angles Between Fusion Faces, , (Clause 10.5.3.2), Angle Between Fusion Faces, , Constant, K, , 60°–900, , 91”–100”, , IOI”--1O6”, , 1070–113°, , I 14“–120°, , 0.70, , 0.65, , 0.60, , 0.55, , 0.50, , 78

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—,,., , IS 800:2007, 10.5.7.1.3 Slot or plug welds, , 10.5.4.3 The effective area of a plug weld shall be, considered as the nominal area of the hole in the plane, of the faying surface. These welds shall not be designed, to carry stresses., , The design shear stress on slot or plug welds shall be, as per 10.5.7.1.1., 10.5.7.2 Site welds, , 10.5.4.4 If the maximum length /j of the side welds, transferring shear along its length exceeds 150 times, the throat size of the weld, tt, the reduction in weld, strength as per the long joint (see 10.5.7.3) should be, considered. For flange to web connection, where the, welds are loaded for the full length, the above limitation, would not apply., 10.5.5 Intermittent, , The design strength in shear and tension for site welds, made during erection of structural members shall be, calculated according to 10.5.7.1 but using a partial, safety factor y~Wof 1.5., 10.5.7.3 Long joints, When the length of the welded joint, lj of a splice or, end connection in a compression or tension element is, greater than 150 t,, the design capacity of weld, (see 10.5.7.1.1), fwd shall be reduced by the factor, , Welds, , 10.5.5.1 Unless otherwise specified, the intermittent, fillet welding shall have an effective length of not, less than four times the weld size, with a minimum, , 0.21., , of 40 mm., , Plw=l.2---#o.o, 10.5.5.2 The clear spacing between the effective lengths, of intermittent fillet weld shall not exceed 12 and 16, times the thickness, of thinner plate joined, for, compression and tension joint respectively, and in no, , where, lj, , case be more than 200 mm., , 10.5.8 Fillet Weld Applied to the Edge of a Plate or, 10.5.8.1 Where a fillet weld is applied to the square, edge of a part, the specified size of the weld should, generally beat least 1.5 mm less than the edge thickness, in order to avoid washing down of the exposed arris, (see Fig. 17A)., , For the purpose of this code, weld shall be fillet, butt,, slot or plug or compound welds. Welding electrodes, shall conform to 1S 814., , 10.5.8.2 Where the fillet weld is applied to the rounded, toe of a rolled section, the specified size of the weld, should generally not exceed 3/4 of the thickness of the, section at the toe (see Fig. 17B)., , 10.5.7 Design Stresses in Welds, 10.5.7.1 Shop welds, , 10.5.8.3 Where the size specified for a fillet weld is, such that the parent metal will not project beyond the, weld, no melting of the outer cover or covers shall be, allowed to occur to such an extent as to reduce the, throat thickness (see Fig. 18)., , 10.5.7.1.1 Fillet welds, Design strength of a fillet weld, ~W~shall be based on, its throat area and shall be given by:, , 10.5.8.4 When fillet welds are applied to the edges of, a plate, or section in members subject to dynamic, loading, the fillet weld shall be of full size with its leg, length equal to the thickness of the plate or section,, with the limitations specified in 10.5.8.3., , t ?’mw, , where, , fu, , =, , f,/&*, , =, , smaller of the ultimate stress of the weld, or of the parent metal, and, , of the, , Section, , 10.5.6 Weld Types and Quality, , f.., , = length of the joint in the direction, force transfer, and, , t, = throat size of the weld., , 10.5.5.3 Unless otherwise specified, the intermittent, butt weld shall have an effective length of not less than, four times the weld size and the longitudinal space, between the effective length of welds shall not be more, than 16 times the thickness of the thinner part joined., The intermittent welds shall not be used in positions, subject to dynamic, repetitive and alternating stresses., , fwd ‘f.., , [, , 10.5.8.5 End fillet weld, normal to the direction of force, shall be of unequal size with a throat thickness not, less than 0.5t, where t is the thickness of the part, as, shown in Fig. 19. The difference in thickness of the, welds shall be negotiated at a uniform slope., , y~~ = partial safety factor (see Table 5)., 10.5.7.1,2 Butt welds, Butt welds shall be treated as parent metal with a, thickness equal to the throat thickness, and the stresses, shall not exceed those permitted in the parent metal., , 10.5.9 Stresses Due to Individual Forces, When subjected, 79, , to either compressive, , or tensile or

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IS 800:2007, , 1.5 mm, , 17A, , 17B, , FIG. 17 FILLETWELDS ON SQUAREEDGE OF PLATEOR ROUNDTOE OF ROLLEDSECTION, , 18A Desirable, , 18B Acceptable because of, Full Throat Thickness, , 18C Not Acceptable because of, Reduced Throat Thickness, , Fm. 18 FULL SIZE FILLETW ELDAPPLIIZDTOTHEEDGE OF A PLATEOR SECTION, , not be done fo~, , shear force alone, the stress in the weld is given by:, , a), , side fillet welds joining, flange plates, and, , b), , fillet welds where sum of normal and shear, stresses does not exceed~W~ (see 10.5.7.1.1)., , faorq=~, where, L=, q, , P=, t,, , 10.5.10.2.1 Check for the combination, , of stresses in, butt welds need not be carried out provided that, , = shear stress, in N/mm*;, (axial force Nor the shear, , = effective throat thickness, , and, , 10.5.10.2 Butt welds, , calculated normal stress due to axial force,, in N/mm*;, , force transmitted, force Q);, , cover plates, , a), , butt welds are axially loaded, and, , b), , in single and double bevel welds the sum of, normal and shear stresses does not exceed the, design normal stress, and the shear stress does, not exceed 50 percent of the design shear, stress., , of weld, in mm;, , and, , lW = effective length of weld, in mm., 10.5.10 Combination of Stresses, , 10.5.10.2.2 Combined bearing, bending and shear, , 10.5.10.1 Fillet welds, , Where bearing stress, fb, is combined with bending, (tensile or compressive), fb and shear stresses, q under, the most unfavorable conditions of loading in butt, welds, the equivalent stress, ~, as obtained from the, following formula, shall not exceed the values allowed, for the parent metal:, , 10.5.10.1.1 When subjected to a combination of normal, and shear stress, the equivalent stress fe shall satisfy, the following:, , & = Jf;, , +f;, , +f, fbr+%’, , where, where, L=, , q, , normal stresses, compression or tension, due, to axial force, or bending, moment, (see 10.5.9), and, , L=, fb, , = shear stress due to shear force or tension (see, 10.5.9)., , 10.5.10.1.2 Check for the combination, , of stresses need, 80, , equivalent, , stress;, , = calculated stress due to bending, in N/mmz;, , fb,, , = calculated, and, , stress due to bearing, in N/mm*;, , q, , = shear stress, in N/mm*.

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IS 800:2007, , CHAMFER, , 1, h, ri, h:b = 1:2 or Flatter, , FORCE, , FORCE, , FIG, 19 END FILLET WELD NORMAL TO DIRECTION OR FORCE, , d), , 10.5.11 Where a packing is welded between two, members and is less than 6 mm thick, or is too thin to, allo”w provision of adequate welds or to prevent, buckIing, the packing shall be trimmed flush with the, edges of the element subject to the design action and, the size of the welds along the edges shall be increased, over the required size by an amount equal to the, thickness of the packing. Otherwise, the packing shall, extend beyond the edges and shall be fillet welded to, the pieces between which it is fitted., , 10.6.1 Connections can be classified as rigid, semi-rigid, and flexible for the purpose of analysis and design as, per the recommendation in Annex F. Connections with, sut%cient rotational stiffness maybe considered as rigid., Examples of rigid connections include flush end-plate, connection, and extended end-plate, connections., Connections with negligible rotational stiffness may be, considered as flexible (pinned). Examples of flexible, connections, include single and double web angle, connections and header plate connections. Where a, connection cannot be classified as either rigid or flexible,, it shall be assumed to be semi-rigid. Examples of semirigid connections include top and seat angle connection, and top and seat angle with single/double web angles., , 10.6 Design of Connections, Each element in a connection shall be designed so that, the structure is capable of resisting the design actions., Connections and adjacent regions of the members shall, be designed by distributing the design action effects, such that the following requirements are satisfied:, a), , Design action effects distributed to various, elements shall be in equilibrium, with the, design action effects on the connection,, , b), , Required deformations in the elements of the, connections are within their deformations, capacities,, , c), , All elements in the connections, and the, adjacent areas of members shall be capable, of resisting the design action effects acting, on them, and, , Connection, elements shall remain stable, under, the design, action, effects, and, deformations., , 10.6.2 Design shall be on the basis of any rational, method supported by experimental evidence. Residual, stresses due to installation of bolts or welding normaily, need not be considered in statically loaded structures,, Connections in cyclically loaded structures shall be, designed considering fatigue as given in Section 13., For earthquake load combinations,, the connections, shall be designed to withstand the calculated design, action effects and exhibit required ductility as specified, in Section 12., 81

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IS 800:2007, 6), , 10.6.3 Beam and column splice shall be designed in, accordance with the recommendation, given in F-2, and F-3., 10.7 Minimum, , Design Action on Connection, , A splice subjected to a shear force only, shall be designed to transmit the design, shear force together with any bending, moment resulting from the eccentricity, of the force with respect to the centroid, of the group., , Connections carrying design action effects, except for, lacing connections, connections of sag rods, purlins, and girts, shall be designed to transmit the greater of, a), , the design action in the member; and, , b), , the minimum design action effects expressed, either as the value or the factor times the, member design capacity for the minimum size, of member required by the strength limit state,, specified as follows:, 1), , 7), , Connections in rigid construction — a, bending moment of at least 0.5 times the, member design moment capacity, to beam, in simple, construction — a shear force of at least, , For earthquake load combinations, the, design action effects specified in this, section may need to be increased to meet, the required behaviour of the steel frame, and shall comply with Section 12., , 0.15 times the member design shear, capacity or 40 kN, whichever is lesser, , Connections at the ends of tensile or, compression member — a force of at least, , 10.8 Intersections, , 0.3 times the member design capacity, 4), , Splices in members subjected to axial, tension — a force of at least 0.3 times, , 5), , Splices in members subjected to axial, compression — for ends prepared for full, , Splices in members subject to combined, actions — a splice in a member subject, to a combination of design axial tension, or design axial compression and design, shall, satisfy, moment, bending, requirements in (4), (5) and (6) above,, simultaneously., , 2)_ Connections, , 3), , Splices injlexural members — a bending, moment of 0.3 times the member design, capacity in bending. This provision shall, not apply to splices designed to transmit, shear force only., , Members or components meeting at a joint shall be, arranged to transfer the design actions between the, parts, wherever practicable, with their centroidal axes, meeting at a point. Where there is eccentricity at joints,, the members and components shall be designed for, the design bending moments which result due to, eccentricity., , the member design capacity in tension, , contact in accordance with 17.7.1, it shall, be permissible, to carry compressive, actions by bearing on contact surf?ces., When members are prepared for full, contact to bear at splices, there shall be, sufficient, fasteners, to hold all parts, securely in place. The fasteners shall be, sufficient to transmit a force of at least, 0,15 times the member design capacity, in axial compression., , The disposition of fillet welds to balance the design, actions about the centroidal, axis or axes for end, connections of single angle, double angle and similar, type members is not required for sta~ally, loaded, members but is required for members, connection, components subject to fatigue loading., Eccentricity, between the centroidal axes of angle, members and the gauge lines for their bolted end, connections may be neglected in statically loaded, members, but shall be considered in members and, connection components subject to fatigue loading., , When members are not prepared for full, contact,, the splice material, and its, fasteners shall be arranged to hold all, parts in line and shall be designed to, transmit a force of at least 0.3 times the, member, design, capacity, in axial, compression., , 10.9 Choice of Fasteners, Where slip in the serviceability, limit state is to be, avoided in a connection,, high-strength, bolts in a, friction-type joint, fitted bolts or welds shall be used., , In addition,, splices located between, points of effective lateral support shall, be designed for the design axial force,, P~ plus a Jesign bending moment, not, less than the design bending moment, M,= (P, /,)/1 000, , Where a joint is subjected to impact or vibration, either, high strength bolts in a friction type joint or ordinary, bolts with locking devices or welds shall be used., 10.10 Connection, , where, /, is the distance between points, of effective lateral support., , Components, , Connection components, 82, , (cleats, gusset plates, brackets

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IS 800:2007, and only bolts in the tension side of the, neutral axis may be considered, for, calculating the neutral axis and second, moment of area., , and the like) other than connectors, shall have their, capacities assessed using the provisions of Sections 5,, 6,7,8 and 9, as applicable., 10.11 Analysis of a Bolt/Weld, , Group, , 2), , In the friction grip bolt group only the, bolts, shall be considered, in the, calculation of neutral axis and second, moment of area., , 3), , The fillet weld group, in isolation from the, for the calculation of, moment of the weld, , 10.11.1 Bolt/Weld Group Subject to In-plane Loading, 10.11.1.1 General method of analysis, The design force in a boltiweld or design force per, unit length in a boltiweld group subject to in-plane, loading shall be determined in accordance with the, following:, a), , b), , c), , shall be considered, connected elemen~, centroid and second, length., , 10.11.2.2 Alternative analysis, , The connection plates shall be considered to, be rigid and to rotate relative to each other, about a point known as the instantaneous, centre of rotation of the group., , The design force per unit length in a fillet weld/bolt, group may alternatively be determined by considering, the fillet weld group as an extension of the connected, member and distributing the design forces among the, welds of the fillet weld group so as to satisfy, equilibrium between the fillet weld group and the, elements of the connected member., , In the case of a group subject to a pure couple, only, the instantaneous, centre of rotation, coincides with the group centroid. In the case, of in-plane shear force applied at the group, centroid, the instantaneous, centre of the, rotation is at infinity and the design force is, uniformly distributed throughout the group., In all other cases, either the results of, independent analyses for a pure couple alone, and for an in-plane shear force applied at the, group centroid shall be superposed,, or a, recognized method of analysis shall be used., , Bolt/Weld Group Subject to In-plane and, Out-of-Plane Loading, , 10.11.3, , 10.11.3.1 General method of analysis, The design force in a bolt or per unit length of the, weld shall be determined, by the superposition, of, analysis for in-plane and out-of-plane cases discussed, in 10.11.1 and 10.11.2., , The design force in a bolt or design force per, unit length at any point in the group shall be, assumed to act at right angles to the radius, from that point to the instantaneous centre,, and shall be taken as proportional, to that, radius., , 10.11.3.2 Alternative analysis, , 10.11.2.1 General method of analysis, , The design force in a bolt or per unit length in the, fillet weld group may alternatively be determined by, considering the fillet weld group as an extension of, the connected member and proportioning the design, force per bolt or unit length in the weld group to satisfy, equilibrium, between the bolt/weld group and the, elements of the connected member., , The design force of a bolt in bolt group or design force, per unit length in the fillet weld group subject to outof-plane loading shall be determined in accordance, with the following:, , Force calculated in the most stressed bolt or highest, force per unit length of the weld shall satisfy the, strength requirements, of 10.3, 10.4 or 10.5, as, appropriate., , 10.11.2, , Bolt/Weld Group Subject to Out-of-Plane, , Loading, , a), , b), , Design force in the bolts or per unit length in, the fillet weld group resulting from any shear, force or axial force shall be considered to be, equally shared by all bolts in the group or, uniformly distributed over the length of the, fillet weld group., , 10.12 Lug Angles, 10.12.1 Lug angles connecting outstanding leg of a, channel-shaped, member shall, as far as possible, be, disposed symmetrically with respect to the section of, the member., 10.12.2 In the case of angle members, the lug angles, and their connections to the gusset or other supporting, member shall be capable of developing a strength not, less than 20 percent in excess of the force in the, outstanding leg of the member, and the attachment of, the lug angle to the main angle shall be capable of, , Design force resulting from a design bending, moment shall be considered to vary linearly, with the distance from the relevant centroidal, axes:, 1), , In bearing type of bolt group plates in, the compression side of the neutral axis, 83

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IS 800:2007, Actual tensile stress, ~ = T,/A~, , developing a strength not less than 40 percent in excess, of the force in the outstanding leg of the angle., , The permissible stress, ~,[ is smallest of the values as, obtained below:, , 10.12.3 In the case of channel members and the like,, the lug angles and their connection to the gusset or, other supporting, member, shall be capable, of, developing a strength of not less than 10 percent in, excess of the force not accounted for by the direct, connection of the member, and the attachment of the, lug angles to the member shall be capable of developing, 20 percent in excess of that force., , a), , As governed by yielding of gross section, ~,= 0.6~, , b), , As governed by rupture of net section, , Plates under tension, &t= 0.69 T,n1A,, 2) Angles under tension, &,= 0.69 T,. 1A,, 1), , 10.12.4 In no case shall fewer than two bolts, rivets or, equivalent welds be used for attaching the lug angle to, the gusset or other supporting member., , c), , As governed by block shear, f,, = 0.69 T,, I A,, , 10.12.5 The effective connection of the lug angle shall,, as far as possible terminate at the end of the member, connected, and the fastening of the lug angle to the, main member shall preferably start in advance of the, direct connection of the member to the gusset or other, suppc”ting member., , where, T,, , = actual, tension, (service) load,, , under, , working, , As = gross area,, , 10.12.6 Where lug angles are used to connect an angle, member, the whole area of the member shall be taken, as effective not withstanding, the requirements, of, Section 6 of this standard., SECTION 11, WORKING STRESS DESIGN, , Tdn, , =, , Tdb, , =, , design, strength, in- tension, of, respective plate/angle calculated in, accordance with 6.3, and, design block shear strength, in, tension of respective, plate/angle, calculated in accordance with 6.4., , 11.3 Compression, , Members, , 11.3.1 Actual Compressive Stress, 11.1 General, 11.1.1 General design requirements, apply in this section., , The actualcompressive stress,~ at working (service) load,, P, of a compression member shall be less than or equal to, , of Section 3 shall, , the permissible compressive stress,fiC as given below:, Actual compressive, , 11.1.2 Methods of structural analysis of Section 4 shall, also apply to this section. The elastic analysis method, shall be used in the working stress design., , The permissible, , stress, fc = P, 1A., , compressive, , stress, f,c = 0.60 fcd, , where, 11.1.3 The working stress shall be calculated applying, respective partial load factor for service load/working, load., , A., , = effective sectional area as defined in 7.3.2,, and, , stress as defined, &d = design compressive, 7.1.2.1 (for angles see 7.5.1.2)., , 11.1.4 In load combinations involving wind or seismic, loads, the permissible, stresses in steel structural, members may be increased by 33 percent. For anchor, bolts and construction, loads this increase shall be, limited to 25 percent. Such an increase in allowable, stresses should not be considered if the wind or seismic, load is the major load in the load combination (such as, acting along with dead load alone)., , in, , 11.3.2 Design Details, Design of the compression, to 7.3., , members, , shall conform, , 11.3.3 Column Bases, The provisions of 7.4 shall be followed for the design, of column bases, except that the thickness of a simple, column base, t$shall be calculated as:, , 11.2 Tension Members, 11.2.1 Actual Tensile Stress, , t,=, , The actual tensile stress, j on the gross area of crosssection, A~ of plates, angles and other tension members, shall be less than or equal to the smaller value of, permissible tensile stresses,jat, as given below:, , 3 w (az– 0.3b2 )\fb,, , where, w, , 84, , = uniform pressure from below on the slab, base due to axial compression;

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IS 800:2007, , a,b=, , 11.4.2, , larger and smaller projection of the slab base, beyond the rectangle circumscribing, the, column, respectively; and, , The actual shear stress, ~~ at working load, V, of a, bending member shall be less than or equal to the, permissible shear stress, ‘r,~given below:, , = permissible bending stress in column base, equal to 0.75fY., , f,,, , Actual shear stress, z~ = V. i A,, , 11.3.4 Angle Struts, , The permissible, , Provisions of 7.5 shall be used for design of angle, struts, except that the limiting actual stresses shall be, calculated in accordance with 11.3.1., , a), , When subjected, , pure sheac, , When subject to shear buckling (see 8.4.2.1):, T,, = 0.70 Vm/Av, , The laced and battened columns shall be designed in, accordance with 7.6 and 7.7, except that the actual, stresses shall be less than the permissible stresses given, in 11.3.1., , where, , Vn, , = design shear strength as given in 8.4.2.2(a), and, , A,, = shear area of the cross-section, in 8.4.1., , 11.4 Members Subjected to Bending, , as given, , 11.4.3 Plate Girder, , 11.4.1 Bending Stresses, The actual bending tensile and compressive, , Provisions of 8.3,8.4,8.5,8.6, and 8.7 shall apply, for, the design of plate girder, except that the allowable, stresses shall conform to 11.4.1 and 11.4.2., , stresses,, , & & at working (service) load moment, M, of a, bending member shall be less than or equaI to the, permissible bending stresses, fabt,.& respectively, as, given herein. The actual bending stresses shall be, calculated as:, and, , 11.4.4 Box Girder, In design of box girder the provisions of 8.8 shall apply,, except that the allowable, bending stresses shall, conform to 11.4.1., , fbt = % /%,, , The permissible bending stresses, ~,~. or f,b~ shall be, the smaller of the values obtained from the following:, a), , shear stress is given by:, , T,, = 0.40 f,, b), , 11.3.5 Laced and Battened Columns, , fk = M. IZ.C, , Shear Stress in Bending Members, , 11.5 Combined, , Stresses, , 11.5.1 Combined Bending and Shear, , Laterally supported beams and beams, bending about the minor axis:, 1) Plastic and compact sections, , Reduction in allowable moment need not be considered, under combined bending and shear., 11.5.2 Combined Bending and Axial Force, , “&,cor&,, = 0.66&, 2) Semi-compact sections, , Members subjected to combined axial compression, bending shall be so proportioned, to satisfy, following requirements:, , JJ.orjt,, = 0.60~, b) Laterally unsupported beams subjected to, major axis bending:, f&= 0.60 M, J Z,C, f,,, = 0.60 M, I Z.t, c) Plates and solid rectangles bending about, minor axis:, , a), , Member stability requirement:, cmyf.y+K, , f, J-+o.6Ky, f, , fix,, , =Y, , %fky, , f, , where, , JatIcy, , Jacz, , = yield stress of the sect; and, , M~, , = design bending, strength, of a, laterally unsupported beam bent, about major axis, calculated in, accordance with 8.2.2., , ‘T Lz-, , ~ K %zfw, , ,~-, , “, , < ~.o, , Jatcz, , where, , z.., Zet= elastic section modulus for the, cross section with respect to, extreme compression and tension, fibres, respectively;, f,, , A<1O, , —, , ++o.6Ky~, , fah =.Lb,= o.75fy, , and, the, , Cmy,Cmz=, k=, fkyfbz, , equivalent, uniform moment, factor as per Table 18,, applied axial compressive stress, under service load,, , stresses, = applied compressive, due to bending about the major, (Y) and minor (z) axis of the, member, respectively,, , 85

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IS 800:2007, -kpfacz, , =, , fabcy .&, , formula, shall not exceed 0.9fY, , allowable, axial compressive, stress as governed by buckling, about minor (y) and major (z), axis, respectively,, , f., , f,’+ f: f;+ 3T;, , where, , = allowable bending compressive, stresses due to bending about, minor (y) and major (z) axes of, the cross-section (see 11.4),, , ‘T, , actual shear stress,, actual tensile stress,, , f,, , Ky = 1 + (kY– 0.2)nY< 1 + 0.8 nY,, , f,, The value, to be used, the values, , Kz = 1 + (l,Z– 0.2)nz S 1 + 0.8 nZ,, O.lk,~ n,, 1-, , = Jf:+, , (C~,, - 0.25) 21, , yield stress, and, actual bearing stress., of permissible bending stresses fbCyand fkz, in the above formula shall each be ‘lesser of, of the maximum allowable stresses f,k and, , fab~in bending about appropriate, , KL~=, , —, , 0.1 ny, , 11.6 Connections, , (CmL, - 0.25) ‘, 11.6.1 All design provisions of Section 10, except for, the actual and permissible stress calculations, shall, apply., , where, , nY nZ = ratio of actual, , applied axial, stress to the allowable axial, stress for buckling about the y, and z axis, respectively;, , c MLT, L,T, , b), , =, , =, , axis., , equivalent, factor; and, , uniform, , non-dimensional, ratio (see 8.2.2)., , 11.6.2 Actual Stresses in Fasteners, , 11.6.2.1 Actual stress in bolt in shear, f,b should be, less than or equal to permissible stress of the bolt, f,,b, as given below:, , moment, , The actual stress in bolt in shear, Lb= V,b/A,b, , slenderness, , Vn,b/A,b, , At a support he values&, and ~,,, shall be, calculated using laterally supported member, and shall satisfy:, , where, , fc, , +fk+f~z<lo, ——, 0.6 fy, fky, fk, , stress in bolt in shear, f2.h, .. = 0.60, , The permissible, , Member strength requirement, , V,b =, , actual shear force under working (service), load,, , Vn,b=, , nominal shear capacity of the bolt as given, in 10.3.3, and, , —., , A,b = nominal plain shank area of the bolt., , 11.5.3 Combined Bending and Axial Tension, , 11.6.2.2 Actual stress of bolt in bearing on any plate,, should be less than or equal to the permissible, bearing stress of the boltiplate, f,pb as given below:, , Members subjected to both axial tension and bending, shall be proportioned so that the following condition, is satisfied:, , fpb, , Actual stress of bolt in bearing on any plate,, fpb = V,blApb, The permissible, , where, lbty,~btz, , bearing stress of the bolt/plate,, &, , = permissible, , tensile, stresses, under, bending about minor (y) and major (z), axis when bending alone is acting, as, given in 11.4.1., , = 0.60 VnP~JAPb, , where, , V~Pb= nominal bearing capacity of a bolt on any, plate as given in 10.3.4, and, A Pb = nominal bearing area of the bolt on any plate., , 11.5.4 Combined Bearing, Bending and Shear Stresses, , 11.6.2.3 Actual tensile stress of the bolt,~b should be, less than or equal to permissible tensile stress of the, , Where a bearing stress is combined with tensile or, compressive stress, bending and shear stresses under, the most unfavorable, conditions, of loading, the, equivalent, stress, f, obtained from the following, , boh,f.,b as given below:, Actual tensile stress of the bolt, ~b = T, / A,b, 86

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IS 800:2007, The permissible, , without premature, , tensile stress of the bolt,, , failure., , 12.2 Load and Load Combinations, where, T<, , =, , tension in boltunder, , Tnb, , =, , design tensile capacity ofaboltas, 10.3.5, and, , 12.2.1 Earthquake loads shall be calculated, IS 1893 (Part 1), except that the reduction, recommen-ded, in 12.3 may be used., , working (service) load,, given in, , 12.2.2 In the limit state design of frames resisting, earthquake loads, the load combinations shall conform, to Table 4., , A,~ = nominal plain shank area of the bolt., 11.6.2.4 Actual compressive or tensile or shear stress, of a weld,~W should be less than or equal to permissible, stress of the weld, ~~Was given below:, The permissible, , 12.2.3 In addition the following load combination shall, be considered, as required, in 12.5.1.1,, 12.7.3.1,, 12.11.2.2 and 12.11.3.4:, , stress of the weld,~,W = 0.6~Wn, , where, jWn = nominal, calculated, , shear, , capacity, , of the weld, , as, , a), , 1.2 Dead Load (DL) + 0.5 Live Load (LL) *, 2,5 Earthquake Load (EL); and, , b), , 0.9 Dead Load (DL) & 2.5 Earthquake, (EL)., , in 10.5.7.1.1., , 11.6.2.5 If the bolt is subjected to combined shear and, tension, the actual shear and axial stresses calculated, in accordance with 11.6.2.1 and 11.6.2.3 do not exceed, the respective permissible stresses ~a,~andf,[b then the, expression given below should satisfy:, , 12.3 Response, , [21+[2]’10, , where, , .f,b,~b = actual, shear and, respectively, and, , tensile, , as per, factors, , stresses, , Reduction, , Load, , Factor, , For structures, designed, and detailed as per the, provision of this section, the response reduction factors, specified in Table 23 may be used in conjunction with, the provision in IS 1893 for calculating the design, earthquake forces., Table 23 Response Reduction Factor, Building System, sl, , Lateral Load Resisting, , (R) for, , System, , R, , No., , i.sbt~aib= permissible ‘hear and tensile ‘tresses, , (1), , (2), , O, , Braced Frame Systems:, a) Ordtnary Concentrically Braced Frames, (OCBF), b) Special Concentrically Braced Frame, (SCBF), Eccentrically Braced Frame (EBF), c), Moment Frame System:, a) OrdinaryMomentFrame(OMF), b) SpecialMomentFrame (SMF), , respectively., 11.6.3 Stresses in Welds, 11.6.3.1 Actual stresses in the throat area of fillet welds, shall be less than or equal to permissible stresses, faw, as given below:, , ii), , faw = 0.4 f,, , 11.6.3.2 Actual stresses in the butt welds shall be less, than the permissible stress as governed by the parent, metal welded together., , 12.4 Connections,, , (?), 4, 4.5, 5, , 4, 5, , Joints and Fasteners, , 12.4.1 All bolts used in frames designed to resist, earthquake loads shall be fully tensioned high strength, friction grip (HSFG) bolts or turned and fitted bolts., , SECTION 12, DESIGN AND DETAILING FOR, EARTHQUAKE, LOADS, , 12.4.2 All welds used in frames designed to resist, earthquake loads shall be complete penetration butt welds,, except in column splices, which shall conform to 12.5.2., , 12.1 GeneraI, Steel frames shall be so designed and detailed as to, give them adequate strength, stability and ductility to, resist severe earthquakes, in all zones classified in, IS 1893 (Part 1) without collapse. Frames, which form, a part of the gravity load resisting system but are not, intended to resist the lateral earthquake loads, need, not satisfy the requirements of this section, provided, they can accommodate, the resulting deformation, , 12.4.3 Bolted joints shall be designed not to share load, in combination with welds on the same faying surface., 12.5 Columns, 12.5.1 Column Strength, When PjP~ is greater than 0.4, the requirements, in 12.5.1.1 and 12.5.1.2 shall be met., 87

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IS 800:2007, Where, , P,, , = required, , compressive, member, and, , strength, , Pd = design, , stress in axial, obtained from 7.1.2., , wit,h importance factor greater than unity (1> 1.0) in, seismic zone III., , of the, , compression, , 12.7.1.2 The provision, in this section apply for, diagonal and X-bracing only. Specialist literature, may be consulted for V and inverted V-type bracing., K-bracing shall not be permitted in systems to resist, earthquake., , as, , 12.5.1.1 The required axial compressive, and axial, tensile strength in the absence of applied moment, shall, be determined from the load combination in 12.2.3., , 12.7.2 Bracing Members, , 12.5.1.2 The required strength determined in 12.5.1.1, need not exceed either of the maximum load transferred, to the column considering, 1.2 times the nominal, strength of the connecting beam or brace element, or, the resistance of the foundation to uplift., , 12.7.2.1 The slenderness, exceed 120., , 12.7.2.2 The required compressive strength of bracing, member shall not exceed 0.8 times P~, where P~ is the, design strength in axial compression (see 7.1.2)., , 12.5.2 Column Splice, , 12.7.2.3 Along any line of bracing, braces shall be, provided such that for lateral loading in either direction,, the tension braces will have to resist between 30 to 70, percent of the total lateral load,, , 12.5.2.1 A partial-joint penetration groove weld may, be provided in column splice, such that the design, strength of the joints shall be at least equal to 200 percent, of the required strefigth., , 12.7.2.4 Bracing cross-section can be plastic, compact, or semi-compact, but not slender, as defined in 3.7.2., , 12.5.2.2 The minimum required strength for each, flange splice shall be 1.2 times j#f as showing Fig., 20, where A~ is the area of each flange in the smaller, connected column., , 12.7.2.5 For all built-up braces, the spacing of tack, fasteners, shall be such that the unfavorable, slenderness ratio of individual element, between such, fasteners, shall not exceed 0.4 times the governing, slenderness ratio of the brace itself. Bolted connections, shall be avoided within the middle one-fourth of the, clear brace length (0.25 times the length in the middle)., , 12.6 Storey Drift, The storey drift limits shall conform to IS 1893. The, deformation compatibility, of members not designed, to resist seismic lateral load shall also conform to, IS 1893 (Part 1)., Pmjn= 1.2 fYA,, , 12.7.2.6 The bracing members shall be designed so that, gross area yielding (see 6.2) and not the net area rupture, (see 6.3) would govern the design tensile strength., , Pmh = 1.2 fyA ,, , t, , of bracing members shall not, , t, , 12.7.3 Bracing Connections, 12.7.3.1 End connections in bracings shall be designed, to withstand the minimum of the following:, A tensile force in the bracing equal to 1.2f#g;, Force in the brace due to load combinations, in 12.2.3; and, , c), , Maximum force that can be transferred to the, brace by the system., , 1[, , JI, , FIG. 20 PARTIALPENETRATION, GROOVEWELD IN, , 12.7.3.2 The connection should be checked for tension, rupture and block shear under the load determined, in 12.7.3.1., , COLUMN SPLICE, , 12.7 Ordinary, (OCBF), , a), b), , Concentrically, , Braced, , Frames, , 12.7.1 Ordinary concentrically braced frames (OCBF), should be shown to withstand inelastic deformation, corresponding to a joint rotation of at least 0.02 radians, without degradation in strength and stiffness below the, full yield value. Ordintuy concentrically braced frames, meeting the requirements, of this section shall be, deemed to satisfy the required inelastic deformation., , 12.7.3.3 The connection shall be designed to withstand, a moment of 1.2 times the full plastic moment of the, braced section about the buckling axis., , 12.7.1.1 Ordinary concentrically braced frames shall, not be used in seismic zones IV and V and for buildings, , 12.8.1 Special concentrically braced frames (SCBF), should be shown to withstand inelastic deformation, , 12.7.3.4 Gusset plates shall be checked for buckling, out of their plane., 12.8 Special Concentrically, , 88, , Braced Frames, , (SCBF)

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IS 800:2007, 12.8.3.4 Gusset plates shall be checked for buckling, out of their plane., , corresponding to a joint rotation of at least 0.04 radians, without degradation in strength and stiffness below the, full yield value. Special concentrically braced frames, meeting the requirements, of this section shall be, deemed to satisfy the required inelastic deformation., , 12.8.4 Column, 12.8.4.1, The column, sections, used in special, concentrically braced frames (SCBF) shall be plastic, as defined in 3.7.2., , 12.8.1.1 Special concentrically braced frames (SCBF), mav. be used in anv. seismic zone [see IS 1893 (Part 1)1, and for any building (importance-factor, value)., , 12.8.4.2, third of, designed, addition,, develop, smaller, nominal, section., , 12.8.1.2 The provision in this section apply for diagonal, and X-bracing only. Specialist, literature, may be, consulted for V and inverted V-type bracing. K-bracing, shall not be permitted in system to resist earthquake., 12.8.2 Bracing Members, 12.8.2.1 Bracing members, steel of IS 2062 only., , shall be made of E250B, , 12.9 Eccentrically, , 12.8.2.2 The slenderness of bracing members shall not, exceed 160 (only hangers)., , Braced Frames (EBF), , Eccentrically braced frames (EBF) shall be designed, in accordance with specialist literature., , 12.8.2.3 The required compressive strength of bracing, member shall not exceed the design strength in axial, compression Pd (see 7.1.2), , 12.10 Ordinary, , Moment, , Frames, , (OMF), , 12.10.1 Ordinary moment frames (OMF) should be, shown, to withstand, inelastic, deformation, corresponding to a joint rotation of 0.02 radians without, degradation in strength and stiffness below the full yield, value (MP). Ordinary moment frames meeting the, requirements of this section shall be deemed to satkfv., the required inelastic deformation., , 12.8.2.4 Along any line of bracing, braces shall be, provided such that for lateral loading in either direction,, the tension braces will resist between 30 to 70 percent, of the load., 12.8.2.5 Braced cross-section, in 3.7.2., , Splices shall be located within the middle onethe column clear height. Splices shall be, for the forces that can be transferred to it. In, splices in columns shall be designed to, at least the nominal shear strength of the, connected member and 50 percent of the, flexural strength of the smaller connected, , shall be plastic as defined, , 12.10.1.1 Ordinary moment frames (OMF) shall not, be used in seismic zones IV and V and for buildings, with importance factor greater than unity (1 > 1.0) in, seismic zone III., , 12.8.2.6 In built-up braces, the spacing of tack, connections shall be such that the slenderness ratio of, individual element between such connections shall not, exceed 0.4 times the governing slenderness ratio of, the brace itself. Bolted connection shall be avoided, within the middle one-fourth of the clear brace length, (0.25 times the length, in the middle)., , 12.10.2 Beam-to-Column Joinls and Connections, Connections are permitted to be rigid or semi-rigid, moment connections and should satisfy the criteria, in 12.10.2.1 to 12.10.2.5., , 12.8.2.7 The bracing members shall be designed so that, gross area yielding (see 6.2) and not the net area rupture, (see 6.3) would govern the design tensile strength., , 12.10.2.1, Rigid moment connections, should be, designed to withstand a moment of at least 1.2 times, of either the full plastic moment of the connected beam, or the maximum moment that can be delivered by the, beam to the joint due to the induced weakness at the, ends of the beam, whichever is less., , 12.8.3 Bracing Connections, 12.8.3.1 Bracing end connections shall be designed to, withstand the minimum of the following:, , 12.8.3.2 The connection should be checked for tension, rupture and block shear under the load determined, in 12.8.3.1., , 12.10.2.2 Semi-rigid connections should be designed, to withstand either a moment of at least 0.5 times the, full plastic moment of the connected beam or the, maximum moment that can be delivered by the system,, whichever is less. The design moment shall be achieved, within a rotation of 0.01 radians. The information given, in Annex F may be used for checking., , 12.8.3.3 The connection shall be designed to withstand, a moment of ’1.2 times the full plastic moment of the, braced section about the critical buckling axis., , 12.10.2.3 The stiffness and strength of semi-rigid, connections shall be accounted for in the design and, the overall stability of the frame shall be ensured., , a), , A tensile force in the bracing equal to 1. l~#~;, and, , b), , Maximum force that can be transferred, brace by the system., , to the, , 89

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IS 800:2007, 12.10.2.4 The rigid and semi-rigid connections should, be designed to withstand a shear resulting from the, load combination, 1.2DL + 0.5LL plus the shear, corresponding, to the design, moment, defined, in 12.10.2.1 and 12.10.2.2, respectively., , A, /, , 12.10.2.5 In rigid fully welded connections, continuity, plates (tension stiffener, see 8.7) of thickness equal to, or greater than the thickness of the beam flange shall, be provided and welded to the column flanges and web., , /, , I, , dp, , 12.11 Special Moment Frames (SMF), , Ti, , bp, , 12.11.1 Special moment frames (SMF) shall be made, of E250B steel of IS 2062 and should be shown to, withstand inelastic deformation corresponding, to a, joint rotation of 0.04 radians without degradation in, strength and stiffness below the full yield value (MP)., , A, , FIG. 21 CONTINUITYPLATES, , Special moment frames meeting the requirements of, this section shall be deemed to satisfy the required, inelastic deformation., , 12.11,2,5 Continuity plates (tension stiffner) (see 8.7), shall be provided in all strong axis welded connections, except in end plate connection., , 12,11.1,1 Special moment frames (SMF) maybe used, in any seismic zone [see IS 1893 (Part 1)] and for any, buildings (importance-factor, values)., , 12.11,3 Beam and Column Limitation, 12.11.3.1 Beam and column sections shall be either, plastic or compact as defined in 3.7.2. At potential, plastic hinge locations, they shall necessarily be plastic., , 12.11.2 Beam-to-Column Joints and Connections, 12.11.2.1 All beam-to-column, connections shall be, rigid (see Annex F) and designed to withstand a, moment of at least 1.2 times the full plastic moment of, the connected beam. When a reduced beam section is, used, its minimum flexural strength shall be at least, equal to 0.8 times the full plastic moment of the, unreduced section., , 12.11.3.2 The section selected for beams and columns, shall satisfy the following relation:, , 12.11.2.2, The connection, shall be designed, to, withstand a shear resulting from the load combination, 1.2DL + 0.5LL plus the shear resulting from the, application of 1.2MP in the same direction, at each end, of the beam (causing double curvature bending). The, shear strength need not exceed the required value, corresponding to the load combination in 12.2.3., , where, , ~MP, , = sum of the moment, column above, centreline; and, , ~MP,, , 12.11.2.3 In column strong axis connections (beam and, column web in the same plane), the panel zone shall, be checked for shear buckling in accordance with 8.4.2, at the design shear defined in 12.11.2.2. Column web, doubler plates or diagonal stiffeners may be used to, strengthen the web against shear buckling., , capacity in the, and below the beam, , = sum of the moment capacity in the, beams at the intersection of the beam and, column centrelines., , In tall buildings, higher mode effects shall be accounted, for in accordance with specialist literature., 12.11.3.3 Lateral support to the column at both top, and bottom beam flange levels shall be provided so as, to resist at least 2 percent of the beam flange strength,, except for the case described in 12.11.3.4., , 12.11.2.4 The individual thickness of the column webs, and doubler plates, shall satisfy the following:, , 12.11.3.4 A plane frame designed as non-sway in the, direction perpendicular to its plane, shall be checked, for buckling, under the load combination specified, in 12.2.3., , t > (dp+bp)/90, where, t, , CONTINUITY, PLATE, , = thickness of column web or doubler plate,, , 12.12 Column, , Bases, , dP = panel-zone depth between continuity plate,, 12.12.1 Fixed column bases and their anchor bolts, should be designed to withstand a moment of 1.2 times, , and, bP = panel-zone, , width between column flanges., , 90

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IS 800:2007, environment, as in normal atmospheric, condition, and suitably protected, against, corrosion (pit depth c 1 mm)., , the full plastic moment capacity of the column section., The anchor bolts shall be designed to withstand the, combined action of shear and tension as well as prying, action, if any., 12.12.2 Both fixed and hinged column bases shall be, designed to withstand the full shear under any load, case or 1.2 times the shear capacity of the column, section, whichever is higher., SECTION 13, FATIGUE, , Structure, exceeding, , is not subjected, 150 “C., , g), , Transverse fillet or butt weld connects plates, of thickness not greater than 25 mm., , h), , Holes shall not be made in members, connections subjected to fatigue., , Fatigue need not be investigated,, in 13.2.2.3, 13.5.1 or 13.6 is satisfied., , 13.1 General, , against fatigue as given in this section,, however not cover the following:, , to temperature, , and, , if condition, , The values obtained from the standard S-N curve shall, be modified by a capacity reduction factor p. when, plates greater than 25 mm in thickness are joined, together by transverse fillet or butt welding, given by:, , Structure and structural elements subject to loading, that could lead to fatigue failure shall be designed, , a), , f), , This shall, , p,=, , (25/tP)025 <1.0, , where, , Corrosion fatigue,, , b), , Low cycle (high stress) fatigue,, , c), , Thermal fatigue,, , d), , Stress corrosion, , tp, , cracking,, , e), , Effects of high temperature, , f), , Effects of low temperature, temperature)., , (> 1500 C), and, , 13.2.2 Design Spectrum, , 13.1.1 For the purpose of design against fatigue,, different details (of members and connections), are, classified under different fatigue class. The design, stress range corresponding to various number of cycles,, are given for each fatigue class. The requirements of, this section shall be satisfied with, at each critical, location of the structure subjected to cyclic loading,, considering relevant number of cycles and magnitudes, of stress range expected to be experienced during the, life of the structure., , 13.2.2.1 Stress evaluation, Design stress shall be determined by elastic analysis, of the structure to obtain stress resultants and the local, stresses may be obtained by a conventional, stress, analysis method. The normal and shear stresses shall, be determined considering all design actions on the, members, but excluding stress concentration due to the, geometry of the detail. The stress concentration effect, is accounted, for in detail category classification, (see Table 26). The stress concentration, however, not, characteristic, of the detail shall be accounted for, separately in the stress calculation., , 13.2 Design, 13.2.1 Reference Design Condition, The standard S-N curves for each detail category are, given for the following conditions:, Detail is located k a redundant load path,, wherein local failure at that detail alone will, not lead to overall collapse of the structure., , b), , Nominal stress history at the local point in, the detail is estimated/evaluated, by a, conventional, method without taking into, account the local stress concentration effects, due to the detail., , c), , Load cycles are not highly irregular., , d), , Details are accessible, regular inspection., , e), , Structure is exposed to only mildly corrosive, , for and subject, , in mm of the thicker plate, , No thickness, correction, is necessary, when full, penetration butt weld reinforcements, are machined, flush and proved free of defect through non-destructive, testing., , (< brittle transition, , a), , = actual thickness, being joined., , In the fatigue design of trusses made of members with, open sections, in which the end connections are not, pinned, the stresses due to secondary bending moments, shall be taken into account, unless the slenderness ratio, (KZfr), of the member is greater than 40., In the determination, of stress range at the end, connections between hollow sections, the effect of, connection, stiffness, and eccentricities, may be, disregarded, provided, a), , to, , 91, , the calculated stress range is multiplied by, appropriate factor given in Table 24(a) in the, case of circular hollow section connections, and Table 24(b) in the case of rectangular, holIow section connections.

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,,,,,,, , ,, , I, , -., , ..,..——, , IS 800:2007, b), , thedesign throat thickness ofiillet weldsin, the joints is greater than the wall thickness of, the connected member., , value, the partial safety factor for loads in the evaluation, of stress range in fatigue design shall be taken as 1.0., 13.2.3.2 Partial safety factor forfatigue strength (Y~fo, , 13.2.2.2 Design stress spectrum, , Partial safety factor for strength is influenced by, consequences of fatigue damage and level of inspection, capabilities., , In the case of loading events producing non-uniform, stress range cycle, the stress spectrum may be obtained, by a rational method, such as ‘rain flow counting’ or, an equivalent method., , 13.2.3.3 Based on consequences, of fatigue failure,, component details have been classified as given in, Table 25 and the corresponding, partial safety factor, for fatigue strength shall be used:, , 13.2.2.3 Low fatigue, Fatigue assessment is not required for a member,, connection or detail, if normal and shear design stress, ranges, f satisfy the following conditions:, , a), , Fail-safe structural component/detail, is the, one where local failure of one component due, to fatigue crack does not result in the failure, of the structure due to availability of alternate, load path (redundant system)., , b), , Non-fail-safe structural component/detail, is, the one where local failure of one component, leads rapidly to failure of the structure due to, its non-redundant nature., , or if the actual number of stress cycles, lV~c,satisfies, , N~C < 5X106, , (), , 27 I ymfi, , 3, , Yrnf, , where, , safety factors for strength and, load, respectively (see 13.2.3), and, , k,,, , %, = Partial, , f, , Table 25 Partial, , Safety Factors, Strength (ymn), (Clause 13.2.3.3), , = actual fatigue stress range for the detail., S1No., , Table 24 (a) Multiplying Factors for Calculated, Stress Range (Circular Hollow Sections), (Clause 13.2.2.1), sl, , No., , Type of Connection, , Chords, , Verticals, , Diagonals, , (1), , (2), , (3), , (4), , (5), , 1.5, , 1.0, 1.8, , 1.3, , 1.0, , 1.2, , 1.65, , 1.25, , i), , Gap, connections, , ii) Overlap, connections, , K type, { N type, K type, { N type, , 1.5, 1.5, 1.5, , Inspection, , and Access, , for Fatigue, , Consequence, , of Failure, , F, , (1), , (2), , i), , Periodic inspection, maintenance and accessibility to, detail is good, Periodic inspection, maintenance and accessibility to, detail is poor, , ii), , I.4, , \, , Fail-Safe, , Non-fail-Safe, , (3), , (4), , 1.00, , 1.25, , 1.15, , 1.35, , 13.3 Detail Category, Table 24 (b) Multiplying Factors for Calculated, Stress Range (Rectangular Hollow Sections), (Clause 13.2.2.1), SI, , Types of Joint, , Chords, , Verticals, , Diagonals, , (2), , (3), , (4), , (5), , K type, , 1.5, , 1.0, , 1.5, , N type, K type, , 1.5, , 2.2, , 1.6, , 1.5, , 1.0, , 1.3, , { N type, , 1.5, , 2.0, , I .4, , Tables 26 (a) to (d) indicate the classification, of, different details into various categories for the purpose, of assessing fatigue strength. Details not classified in, the table may be treated as the lowest detail category, of a similar detail, unless superior fatigue strength is, proved by testing and/or analysis., , No., , (1), i), , Gap, connections, , ii) Overlap, connections, , {, , Holes in members and connections, loading shall not be made:, a), , using punching in plates, greater than 12 mm unless, punched and subsequently, the affected material around, and, , b), , using gas cutting unless the holes are reamed, to remove the material in the heat affected, zone., , 13.2.3 Partial Safety Factors, 13.2.3.1 Partial safety factor for actions and their, etiects (fifl), Unless and otherwise the uncertainty in the estimation, of the applied actions and their effects demand a higher, 92, , subjected to fatigue, , having thickness, the holes are subreamed to remove, the punched hole,

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IS 800:2007, 13.4 Fatigue Strength, , ~=j.o, , The fatigue strength of the standard detail for the, norroal or shear fatigue stress range, not corrected for, effects discussed in 13.2.1, is given below (see also, Fig. 22 and Fig. 23):, a), , b), , N~c<5, , $=.fk, , when, , Shear stress, , where, , X 106, , r 5xlo, , J, ~t = design normal and shear fatigue s~ess, range of the detail, respectively, for, life cycle of N~c, and, , fN~C, , ~~n,t~n= normal and shear fatigue strength, of the detail for 5 x 10” cycles, for, the detail category (see Table 26)., , 5 x 106 S Nsc S 108, , Table 26 (a) Detail Category Classification, Group 1 Non-welded, (Clauses 13.2.2.1 and 13.3), , SI, No., , Detail, Category, , (1), , (~), , IN,C, , ~~ =7~n55x10elN~c, r, , Normal stress range, when, , Y 5xI0, , Constructional, , Details, , Details, , Illustration (see Note), , Description, , (3), , (4), Rolled and extruded products, , -’, , 1!, ::::::::%), iii), , (1), , Sharp edges, surface and rolling flaws to be, removed by grinding in the direction of applied, , a, , i), , “8, , %, , Seamless tubes (3), , Q, , ‘2), , ‘tress, , (3), , (4) and (5): Stress range calculated on the, gross section and on the net section, connections, ‘“’te:=:, , ‘4)4X, ., , ., ., , ii), , I 03, , the, , ., ., , ., ., >., , calculating stresses, , Material with gas-cut or sheared edges with no, draglines, (6): All hardened material and visible signs, , . ., . ., . ., \, , (5), , shall be avoided or the effect of, one-sided, cover, ‘ate, eccentricity, taken into account in, , of edge discontinuities to be removed by, machining or grinding in the direction of, applied stress., , s, , (Material with machine gas-cut edges, draglines or manual gas-cut material, , iii), , 92, , with, , (7) : Corners and visible signs of edge, discontinuitiesto be removed by grinding in the, directionof the appliedstress., , =, , NOTE— The arrow indicates the location and direction of the stresses acting in the basic material for which the stress range is to be, calculatedon a plane normal to the arrow., , 93

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IS 800:2007, Table 26 (b) Detail Category, , Classification,, , Group 2 Welded, Details — Not in Hollow Sections, , (Clauses 13.2.2.1 and 13.3), , SI, {0., , ,1), , Constructional, , Detail, Category, , Details, , Illustration(seeNote), , Description, , (3), , (4), , (2), , Welded plate I-section and, continuous longitudinal welds, ~, , i), , with, , (8)a(9):mnmof~ntinuousautomatic, longitudinal fillet or butt welds carried out from both, sides and all welds not having un-repaired stop-start, positions., , QA, , (8), , 92, , box girders, , Q, Welded plate I-section and, continuous longitudinal welds, , box girders, , with, , (10) & (11) : Zones of continuous automatic butt, welds made tlcsm one side only with a continuous, backing bar and all welds not having un-repaired, ,,,, , *, , stoP-s@positions, , a’k, , (11), , (lo), , m, , (12), , Welded plate I-section and, continuous longitudinal welds, , “., , iii), , (12) : Zones of continuous longitudinal fillet or butt, welds carried out fkom both sides but containing, stop-start positions. For continuous manual, longitudinal tilIet or butt welds carried out from both, sides, use Detail Category 92., girders, , with, , (13) : Zones of continuous longitudinal welds carried, out ffom one side only, with or without stop-start, , 66, Q, , positions., , (13), , Intermittent, , iv), , box, , Q, , longitudinal, , welds, , (14) : Zones of intermittent longitudinal welds, , “., , r, , 59, , (14), , intermittent, \, , v), , (15), , Transverse, , 83, , (16) : Transverse splices in plates, flats and rolled, sections having the weld reinforcement ground flush, to p}ate surface. 100 percent NDT inspection, and, weld surface to be ffee of exposed porosity in the, weld metal., , a, , —-, , (17), , (18), , butt welds (complete penetration), , Weld run-off tabs to be used, subsequently removed, and ends of welds ground flush in the direction of, stress. Welds to be made from two sides., , \, , vi), , welds, , welded T-joints. Cope hole not to be tilled with, weld., , 52, , Q, , longitudinal, , (15) : Zones containing cope holes in longitudinally, , (17) : Plate girders welded as in (16) before, assembly., , =(la), , (18) : Transverse splices as in (16) with reduced or, tapered transition with taper S1:4, , 94

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..______, , ~, , IS 800:2007, Table 26 (b) (Continued), , 51, io., , Detail, Category, , 1), , (2), , Constructional, , Detaits, , Illustration (see Note), , Description, , (3), , (4), Transverse, , butt welds (complete penetration), , Welds inn-off tabs to be used, subsequently removed, , and ends of welds ground flush in the direction of, stress. Welds to be made from two sides., , \~, (19), , iii), , : Transverse splices of plates, rolled sections or, plate girders., , (19), (20), , 66, , (20) : Transverse splice of rolled sections or welded, plate girders, without cope hole. With cope hole use, Detail Category 52, asin(15)., -’k, , (21): Transversesplices in plates m flats bekrgtapcmd, in width or in tldcknesswherethe taper iss 1:4., , (21), , Transverse, , 59, , /iii), , butt welds (complete penetration), , Weld run-off tabs to be used, subsequently removed, and ends of welds ground flush in the direction of, stress. Welds to be made from two sides., , .-, , : Transverse splices as in (21) with taper in, width or thickness >1:4 but <1:2.5., , (22), , (22), , Transverse, , butt welds (complete penetration), , (23) : Transverse butt-welded splices made on a, backing bar. The end of the fillet weld of the backing, , I-, , strip shall stop short by more than 10 mm from the, ix), , 52, , ~, , ~fim, , e~l, , :::::’:, (24): Transverse butt welds as per (23) with taper on, , Transverse, , butt welds (complete penetration), , (25) : Transverse butt welds as in (23) where fillet, welds end closer than 10 mm to plate edge., , x), , 37, , \, , ~4=’Omm, (25), , Cruciform joints with load-carrying, , welds, , (26) : Full penetration welds with intermediate plate, , NDT inspected and free of defects. Maximum, misalignment of plates either side of joint to be, <0.15 times the thickness of intermediate plate., , xi), +, , 52, , (26), , (27) : Partial penetration or fillet welds with stress, range calculated on plate area., (28) : Partial penetration or fillet welds with stres:, range calculated on throat area of weld., , xii), :, , ‘:, , :*, (27)6 (28), , Overlapped, , ~iii), , 46, , welded joints, , with welds arrc, overlapping elements having a design capacit), greater than the main plate. Stress in the main platt, to be calculated on the basis of area shown in th{, illustration., (29), , --”’, , (29), , 95, , : Fillet welded lap joint,

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IS 800:2007, Table 26 (b) (Concluded), , SI, No., , Detail, Category, , (1), , (2), , Constructional, , Details, , Illustration (see Note), , Description, , (3), , (4), Overlapped, , xiv), , 41, , (30) : Fillet welded lap joint, with welds and main, , (30), , T, , plate both having a design capacity greater than the, overlapping elements., , \, , >lOmm, , ‘w, , xv), , (31), , 33, 66, 59, , x~i), , weld joints, , b, , (32), , (33), , —, , 1/3 < r/b, —, , h,, ‘7, , 52, , ls50mm, 50</ <100 mm, , l16<r/b<l13, , 37, , 100 mm <1, , —, , 33, , (31) : Fillet welded lap joint, with main plate and, overlappingelementsboth having a design capacity, greater than the weld., , (30)a (31), , —, , (non-load carrying welds) —, , (32) : Longitudinal fillet welds. Class of detail varies, according to the length of the attachment weld as, noted., , \, Q, (32), , (33) : Gusset welded to the edge of a plate or beam, flange. Smooth transition radios (r), formed by, machining or flame cutting plus grinding. Class of, detail varies according to r)b ratio as noted., , ‘*, , r/b<l/6, , Welded attachments, Longitudina[welds, , M, , (33), Welded attachments, , xvii), , 59, , (34) : Shear connectors on base material (failure in, base material)., , m, (34), , —, , Transverse, 59, , welds, , (35) : Transverse fillet welds with the end of the, , t<12mm, , weld 210 mm from the edge of the plate., (36) : Vertical stiffeners welded to a beam or plate, girder flange or web by continuous or intermittent, welds. to the case of webs carrying combined, bending and shear design actions, the fatigue, strength shall be determined using the stress range of, the principal stresses., , (35), , xviii), 52, , ZIomm, , t~12mm, , (37) : Diaphragms of box girders welded to the, flange or web by continuous or intermittent welds., , (36), , ~.=., , \, ;! . j:, , w, (37), , 37, xix), , 27, , rfor tp, <25 mm, , \, , ‘p, 1,, , ff m tP, , a, , >25 mm, , (38), , Cover plates in beams and plate girders, , End zones of single or multiple welded cover, plates, with or without a weld across the end. For a, reinforcing plate wider than the flange, an end weld, is essential., , (38) :, , Welds loaded in shear, (39) : Filletweldstransmittingshear. Stressrangeto, xx), , 67, , be calculated on weld throat area., , ~i, (40), , (39), , (40) : Stud welded shear connectors (failure in the, weld) loaded in shear (the shear stress range to be, calculated on the nominal section of the stud)., , NOTE — The arrow indicates the location and direction of the stresses acting in the basic material for which the stress range is to be, calculated on a plane normal to the arrow., , 96

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...-.______, , —-,., , IS 800:2007, Table 26 (c) Detail Category Classification,, (Clauses 13.2.2.1 and 13.3), , sl, No., (1), , Group 3 Bolts, , Constructional, , Details, , Detail Category, Illustration, (2), , [see, , Note, , ), , Description, (4), , (3), , Bolts in shear (8.8fTB bolting category only), (41) : Shear stress range calculated on the, minordiameterarea of the bolt (J,)., , i), , NOTE — If the shear on the joint is, insufficient to cause slip of the joint the, , 83, , shear in the bolt need not reconsidered in, fatigue., , =17-, , (41), Bolts and threaded rods in tension (tensile, stress to be calculated on the tensile stress, area, A,), , t, , +, , (42) : Additional forces dueto prying effects, shall be taken into account. For tensionalbolts,, , ii), , the stress range depends on the connection, geometry., NOTE — In connections with tensioned, bolts, the change in the force in the bolts is, often less than the applied force, but this, effect is dependenton thegeometty of the, connection.It isnotnormally requiredthat, any allowance for fatigue be made in, , 27, Uo, , i, , i, , calculating the required number of bolts in, such connections., , (42), , NOTE— The arrow indicates the location and direction of the stresses acting in the basic material for which the stress mnge is to be, calculated on a plane normal to the arrow., , 1000, , Stress range corresponding, , ..-, , to 2X106 cycles, \, , II, , 20, , - at 5x106 eyeles, [Detail category, , 1, 0 105, , 2, , 34561062, , 1, , (, , fm)], , t I 1 I, 34561072, , 1, 3456108, , NUMBEROF STRESS CYCLES (fJsc), , FIG. 22 S-N CURVEFOR NORMAL STRESS, 97

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Table 26 (d) Detail Category Classification, Group 4, Welded Details in Hollow Sections, (Clause 13.2.2.1 and 13.3), sl, , Detail Category, , Constructional, , No., (1), , Details, , Illustration (see Note), , Description, , (3), , (4), , (2), 103, , Continuous, , automatic longitudinal, , welds, , (43) : No stop-starts, or as manufactured, proven free to, i), Q%, , ‘etachab’ediscontinuities”, (43), , 66, (t> 8 mm), , ii), , Transverse, , butt welds, , (44) : Butt-welded end-to-end connection of circular, hollow sections., , 52, (r< 8 mm), , ae, , Height of the weld reinforcementless, than 10 percent of weld with smooth transitionto, the plate surface. Welds made in flat position and, , NOTE —, , (44), , proven free to detachable discontinuities., , iii), , 52, (t> 8 mm), , t, B, , 41, (t< 8 mm), , (45), , 41, , Butt welds to intermediate, , mm), , (t28, , (45) : Butt-welded end-to-end connection Ofrectangular, hollow sections, , iv), , !3:D, , (t< Vmm), , plate, , (46) : Circular hollow sections, end-to-end butt-welded, with an intermediate plate., , ~, (46), , (47) Rectangular hollow sections, end-to-end butt, welded with art intermediate plate, , 37, (t> 8 mm), =~, , v), 30, (f< 8 mm), , (47), , Welded attachments (non-load-carrying), (48) : Circular or rectangular hollow section, fillet, welded to another section, Section width parallel to, vi), , 52, , s~essdrection~,oomrn, , %77, J, , ~EcTlc)NwcmH, <1 OOmm, (48), , 33, (t< 8, , Fillet welds to intermediate, , mm), rzj, , vii), (t< ?mm), , Q, , (49), , 29, (/> 8 mm), viii), , 27, (t< 8 mm), , plate, , (49) : Circularhollowsections,end-to-endfillet welded, with an intermediateplate., , (50) : Rectangular hollow sections, end-to-end fillet, welded with an intermediate plate., , Ixj, , Q, (50), , NOTE — The arrow indicates tbe location and direction of the stresses acting in the basic material for which the stress range is to be, calculated on a plane normal tO the arrow., , 98

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-_, , IS 800:2007, 13.5 Fatigue Assessment, , 13.5.2.3 Constant stress range, , The design fatigue strength for Nsc life cycles ~fd! ‘fd), may be obtained from the standard fatigue strength, for Nsc cycles by multiplying with co~ection factor,, p,, for thickness, as mentioned in 13.2.1 and dividing, by partial safety factor given in Table 25., , The actual normal and shear stress range f and z at a, point of the structure subjected to Nsc cycles in life, shall satisfy., f ‘ffd = ~r~lymft, T S ‘fd = #r ‘f ‘Ymft, , 13.5.1 Exemptions, where, At any point in a structure if the actual normal and, shear stress range~and ~ are less than the design fatigue, strength range corresponding to 5 x 106 cycles with, appropriate partial safety factor, no further assessment, for fatigue is necessary at that point., , v,, , factor (see 13.2.1),, , partial safety factor against fatigue failure,, given in Table 25, and, , fi, Tf = normal and shear fatigue strength ranges for, the actual life cycle, Nsc, obtained from 13.4., 13.5.2.4 Variable stress range, , 13.5.2.1 The maximum (absolute) value of the normal, and shear stresses shall never exceed the elastic limit, , Fatigue assessment at any point in a structure, wherein, variable stress ranges jfi or 7$ for ni number of cycles, (i =1 to r ) are encountered, shall satisfy the following:, , (f,, ~,) for the material under cyclic loading., stress range shall not exceed, , 1.5$ for normal stresses and 1.5 f,ifi, stresses under any circumstance., , =, , 71nf, , 13.5.2 Stress Limitations, , 13.5.2.2 The maximum, , = correction, , For normal stress (f), , a), , for the shear, , 1000, , 500, g 400, A, >’ 300, s, !If, z, 200, UJ, K, 1fn, Lu, 5, i=, $, 0, , IJJ, 1-, , Q, !JJ, , cc, , cateaotv TI --H_Hk, , 40 ~~Detail, , I, , I, , 1 I, , I, , I, , o 105, , 2, , 34561062, , I, , I I I II, , I, , I, , I, , I, , 1, 34561072, , I I, , NUMBER OF STRESS CYCLES, FIG., , I, , I II, , I, , I, , 3456108, (N~c ), , 23 S-N CURVE FOR SHEAR STRESS, 99, , [, , I, , I, , I I I

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IS 800:2007, 1/3, , I, ~, , n,f,’ + ~ njffi’, , &q = ‘=’, , b), , For shear stresses (t), , where, , ‘=~n, ,=1, , n’=”, , “, , I-I, , ffi>fg = stress ranges falling above and, below the f~n, the stress range, corresponding, to the detail at, 5 x 106 number of life cycles., , where yf is the summation, upper limit of all the, normal stress ranges ~,) having magnitude lesser, than (pC~~n/y~~t)for that detail and the lower limit of, all the normal stress ranges ~j) having magnitude, greater than (PC~#y~~t) for the detail. In the above, summation all normal stress ranges, f,, and Zi having, magnitude less than 0.55pC ~fn, and 0.55pC qn may, be disregarded,, , DESIGN, , SECTlON, ASSISTED, , 14, BY TESTING, , 14.1 Need for Testing, 13.6 Necessity for Fatigue Assessment, a), , 1), , Members, loads,, , 2), , Member subjected to repeated, cycles from vibrating machinery,, , 3), , Members subjected, to wind induced, oscillations of a large number of cycles, in life, and, , 4), , b), , Testing of structures, members or components of, structures is not required when designed in accordance, with this standard. Testing may be accepted as an, alternative to calculations or may become necessary, in special circumstances., , Fatigue assessment is not normally required, for building structures except as follows:, supporting, , lifting, , or rolling, , Testing of a structural system, member or component, may be required to assist the design in the following, cases:, , stress, , a), , When the calculation methods available are not, adequate for the design of a particular structure,, member or component,, testing shall be, undertaken in place of design by calculation, or to supplement the design by calculation;, , b), , Where rulesor, methods, for design by, calculation, would lead to uneconomical, design, experimental, verification, may be, undertaken to avoid conservative design;, , c), , When the design or construction is not entirely, in accordance with sections of this standard,, experimental verification is recommended;, , ‘r~,~,,, , d), , When confirmation, is required, on the, consistency, of production, of material,, components, members or structures originally, designed by calculations or testing; and, , The total number of actual stress cycles, NSC,satisfies, , e), , When the actual performance of an existing, structure capacity is in question, testing shall, be used to confirm it., , Members subjected to crowd induced, oscillations of a large number of cycles, in life., , No fatigue assessment is necessary if any of, the following conditions is satisfied., 1), , The highest, satisfies, , normal, , stress range ~~,~,,, , L, M., ~ 27PcJYmft, 2), , The highest, satisfies, , shear, , stress, , range, , ‘rf,Max<, - 67/-4 /ymft, 3), , N,c S5x10’, , [1, , 3, , 27pC, —, , 14.1.1 Testing of structural, system, member, component shall be of the following categories:, , Ymftffq, , a), , where, J%, = equivalent constant amplitude, stress range in MPa given by, , 100, , or, , Proof testing — The application of test loads, to a structure,, sub-structure,, member or, connection, to ascertain, the structural, characteristics of only that specific unit.

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., , —---%.., , ~~, ---------—-——, , IS 800:2007, b), , Prototype testing — Testing of structures, sub-, , IS 1608) tests . The mean value of the yield strength,, ~Y~,taken from such tests shall be determined with due, regard to the importance, of each element in the, assembly. The strength test load F~e,~,,(including self, weight) shall be determined from:, , structures, members or connections is done, to ascertain the structural characteristics of a, class of such structures,, sub-structures, members or connection, which are nominally, identical to the units tested., , Ftest,s = YmiFd ~ymyy), , 14.2 Types of Test, 14.2.1 Acceptance, , where, Test, , ~Y = characteristic yield stress of the material as, assumed in the design,, , This is intended as a non-destructive test for confirming, structural performance. It should be recognized that, the loading applied to certain structures might cause, permanent distortions. Such effects do not necessarily, indicate structural failure in acceptance test. However,, the possibility of their occurrence should be agreed to, before testing., , Fd = factored design load for the ultimate limit, state, and, %i, , = (1.0x self weight)+ (1.15 x remainder, of the permanent load)+ ( 1.25 x variable, load)., , The assembly shall satisfy the following, , 14.2.3 Test to Failure (Ultimate Strength Test), The objective of a test to failure is to determine the, design resistance from the ultimate resistance. In this, situation it is still desirable to carry out the acceptance, and strength tests, before test to failure., , criteria:, , a), , It shall demonstrate, substantially, behaviour under test loading, and, , b), , On removal of the test load, the residual, deflection shall not exceed 20 percent of the, maximum-recorded, deflection., , linear, , Not less than three tests shall be carried out on, nominally identical specimens. An estimate should be, made of the anticipated ultimate resistance as a basis, for such tests. During a test to failure, the loading shall, first be applied in increments up to the strength test, load. Subsequent, load increments, shall then be, determined from consideration of the principal load, deflection plot. The test load resistance, Ft.,,.R shall be, determined as that load at which the specimen is unable, to sustain any further increase in load. At this load,, gross permanent distortion is likely to have occurred, and in some cases such large gross deformation may, define the test limit. If the deviation of any individual, test result exceeds 10 percent of the mean value, obtained for all the three tests, at least three more tests, shall be carried out. When the deviation from the mean, does not exceed 10 percent of the mean, the design, resistance may be evaluated as given below:, , If the above criteria are not satisfied the test may be, repeated one more time only, when the assembly shall, satisfy the following criteria:, a), , It shall demonstrate, substantially, behaviour on the second application, loading, and, , b), , Corresponding recorded residual deflection, in the second test shall not exceed 10 percent, of the maximum deflection during the test., , partial safety factor for the type of failure,, as prescribed in this standard., , At this load there shall be no failure by buckling or, rupture of any part of the structure or component tested., On removal of the test load, the deflection should, decrease by at least 20 percent of the maximum, deflection at F1.,t,,., , The load for acceptance test, Ftcfi[,.shall be determined, from:, F,.,,,,, , =, , linear, of test, , 14.2.2 Strength Test, Strength test is used to confirm the calculated resistance, of a structure or component. Where a number of items, are to be constructed to a common design, and one or, more prototypes are tested to confirm their strength,, the others may be accepted without any additional test,, provided they are similar in all relevant respects to the, prototype., , a), , When the failure is ductile,, the design, resistance, F~ may be determined from:, , Fd = 0.9F,,,,,~in(fY~Y~) /Y~O, where, , Before carrying out the strength test, the specimen, should first be subjected to and satisfy the acceptance, test. Since the resistance of the assembly under test, depends on the material properties, the actual yield, strength of all the steel materials in the assembly shall, be determined from coupon (test piece as defined in, , F,~,,,~in = minimum test result from the tests, to failure,, , f,. = average yield strength as obtained, from the material tests, and, , 101

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IS 800:2007, ~=, b), , characteristic yield stress of the, grade of steel., , In the case of a sudden (brittle) rupture type, failure, the design resistance, may be, determined from:, , recorded during the acceptance test on the prototype, and the residual deflection should not be more than, 105 percent of that recorded for the prototype., 14.3 Test Conditions, , F~ = 0.9F’,~~,,~in(~U/j&) / &, where, , Loading and measuring, calibrated in advance., , b), , The design of the test rig shall be such that:, , shall be, , f urn = average ultimate tensile strength of, the material obtained from tests., , Loading system adequately simulates the, magnitude, and distribution, of the, loadlng;, , 2), , In the case of a sudden (brittle) buckling type, failure,, the design resistance, shall be, determined from:, , It allows the specimen, manner, representative, conditions;, , 3), , Lateral and torsional restraint, if any,, should be representative of those in service,, , 4), , Specimen should be free to deflect under, load according to service condition;, , 5), , Loading system shall be able to follow, the movements of the specimen without, interruption or abnormal restraints; and, , 6), , Inadvertent eccentricities at the point of, application of the test loads and at the, supports are avoided,, , ultimate stress of the, grade of steel used, and, , F~ = 0,75Fki, Min(~~!~~) /~mO, d), , devices, , 1), , = characteristic, , f“, , c), , a), , In ductile buckling type failure in which the, relevant slenderness k can be reliably assessed,, the design resistance may be determined from:, F. =, , 0.9F .3(,M”[(tiy %fym)%l, , where, x, , = reduction factor for the relevant, buckling curve, and, , x., , = value of x when the yield strength, isfy”., , 14.2.4 Check Tests, Where a component or assembly is designed on the, basis of strength tests or tests to failure and a production, run is carried out of such items, an appropriate number, of samples (not less than two) shall be selected from, each production batch at random for check tests., 14.2.4.1 The samples shall be carefully examined to, ensure that they are similar in all respects to the, prototype tested, particular attention being given to the, following:, a), , Dimensions, , of components, , b), , Tolerance and workmanship;, , c), , Quality of steel used, checked with reference, to mill test certificates., , to perform in a, of service, , c), , Test load shall be applied to the unit at a rate, as uniform as practicable., , d), , Deflections should be measured at sufficient, points of high movements to ensure that the, maximum value is determined., , e), , If the magnitude of stresses in a specimen is, to be determined, the strain at the desired, location, may be measured, and the, corresponding stress calculated., , f), , Prior to any test, preliminary loading (not, exceeding the characteristic, values of the, relevant loads) may be applied and then, removed, in order to set the test specimen on, to the test rig., , 14.4 Test Loading, 14.4.1 Where the self-weight of the specimen is not, representative of the actual permanent load in service,, allowance for the difference shall be made in the, calculation of test loads to be applied., , and connections;, and, , 14.4.2 On the attainment of maximum load for either, acceptance, or strength, tests, this load shall be, maintained, for at least 1 h. Reading of load and, deflection shall be taken at intervals of 15 min and the, loading shall be maintained constant until there is no, significant increase in deflection during a 15 min period, or until at least 1 h has elapsed., , 14.2.4.2 Where it is not possible to determine either, the variations or the effect of variations from the, prototype, an acceptance test shall be carried out as a, check test., 14.2.4.3 In this check test, the deflections shall be, measured at the same positions as in the acceptance, test of the prototype., The maximum, measured, deflection shall not exceed 120 percent of the deflection, , 14.4.3 The test load shall be equal to the design load, for the relevant limit state in proof testing., , 102

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., , _, , —----%.., , IS 800:2007, 14.4.4 The test load in prototype testing shall be equal, to the design load for the relevant limit state as, multiplied by the appropriate factor given in Table 27., Table 27 Factors to Allow for Variability, Structural Units, SI, , of, , No., , No. of Similar, Units to be Tested, , For Strength, Limit State, , (1), , (2), , (3), , (4), , i), ii), iii), , 1, 2, 3, 4, 5, 10, , 1.5, , 1.2, 1.2, 1.2, 1.1, I.1, , iv), , v), , vi), 14.5 Criteria, , structures should be such that good drainage of water, is ensured., Standing, pool of water, moisture, accumulation, and rundown of water for extended, duration shall be avoided., The details of connections, , For, Serviceability, Limit State, , 1.4, 1.3, 1.3, 1.3, I .2, , should ensure that:, , a), , AII exposed surfaces are easily accessible for, inspection and maintenance; and, , b), , All surfaces, not so easily accessible are, completely sealed against ingress of moisture., , 15.2.2 Exposure Condition, , 15.2.2.1 General environment, The general environment, to which a steel structure is, exposed during its working life is classified into five, levels of severity, as given in Table 28., , 1.1, , for Acceptance, , Table 28 Environmental, , 14.5.1 Acceptance for Strength, The test structure, sub-structure, member or connection, shall be deemed to comply with the requirements for, , S1, No., , strength, , (1), , if it is able to sustain, , the strength, , test load for, , Environmental, Classifications, , i) Mild, , It shall then be inspected to determine the nature and, extent of any damage incurred during the tes~ The, effects of the damage shall be considered, and if, necessary appropriate repairs to the damaged parts, carried out., , ii) Moderate, , iii), , Severe, , exposed to condensation and rain, continuously under water, exposed to non-aggressive soiti, groundwater, d) sheltered from saturated salt air in, coastal areas, Structural steel surfaces:, a), b), , SECTION 15, DURABILITY, iv), , Very, , severe, , 15.1 General, , exposed to severe frequent rain, exposed to alternate wetting and, drying, c) severe condensation, d) completely immersed in sea water, e) exposed to saturated salt air in, coastal area, Structural steel surface exposed to:, a), b), c), , is one that performs, A durable steel structure, satisfactorily, the desired function in the working, environment under the anticipated exposure condition, during its service life, without deterioration of the crosssectional area and loss of strength due to corrosion. The, material used, the detailing, fabrication, erection and, surface protection measures should all address the, corrosion protection and durability requirements., , v), , Extreme, , sea water spray, corrosive fumes, aggressivesub soil or ground water, , Structural steel surfaces exposed to:, O, b), , tidal zones and splash zones in the, sea, aggressive liquid or solid chemicals, , 15.2.2.2 Abrasion, Specialist literature may be referred for durability of, surfaces exposed to abrasive action as in machinery,, conveyor belt support system, storage bins for grains, or aggregates., , for Durability, , The design, fabrication, , Structural steel surfaces:, a), b), c), , The maximum deformation of the structure or member, under the serviceability limit state test load shall be, within the serviceability limit values appropriate to the, structure., , 15.2.1 Shape, Size, Orientation, Connections and Details, , (3), , Surfaces normally protected against, exposure to weather or aggressive, condition as in interior of buildings,, except when located in coastal areas, , 14.5.2 Acceptance for Serviceability, , 15.2 Requirements, , Conditions, , Exposure Conditions, , (2), , at least 15 min., , Exposure, , of Members,, , and erection details of exposed, , 103

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IS 800:2007, 15.2.2.3 Exposure to sulphate attack, , and IS 9172. The main corrosion, are given below:, , Appropriate coatings may be used when surfaces of, structural, steel are exposed to concentration, of, sulphates (SOJ) in soil, ground water, etc., When exposed to very high sulphate concentrations, of more than 2 percent in soil and 5 percent in water,, some form of lining, such as polyethylene,, polychloroprene, sheet or surface coating based on, asphalt, chlorinated rubber, epoxy or polymethane, material should be used to completely avoid access of, the solution to the steel surface., , SI, , b), , Inhibitors,, , c), , Inorganic/metal, systems., , and, , Coating System, , Normalinland(ruraland urban, areas),mild, ii) Pollutedinland (high airborne, i), , 1, , 2, , 3, , 4, , 5, , Y, 6, , (3), , (4), , (5), , (6), , (7), , (8), , 12 years, , 18 years, , 20 years, , 10years, , 15years, , 12years, , About, 20 years, About, , 10 years, , 12 years, , 20 years, , About, , sulphur dioxide), moderate, Normal, , coastal, , (as normal, , Polluted, coastal, (as polluted inland, plus high airborne salt levels), very, severe or extreme, , Table 29 (b) (i) Protection, , SI, , (1), , i), ii), , 8 years, , 10 years, , 10 years, , About, 15years, , Guide for Steel Work Application — Specification, System (Shop Applied Treatments), (Clause 15.2.4. 1), , 20 years, 15-20 years, About, 20 years, 15-20 years, , for Different, , Above, 20 years, Above, 20 years, Above, 20 years, Above, 20 years, , Coating, , Coating System, c, , (2), , 1, , 2, , 3, , 4, , 5, , 6, , (3), , (4), , (5), , (6), , (7), , (8), , iv), , Surface preparation Blast clean, Pre-fabrication, Zinc phosphate, primer, epoxy, 20 w, Post-fabrication, High-build zinc, primer, phosphate, modified alkyd,, 60pm, —, Intermediate coat, , v), , Top coat, , iii), , 20 years, , Protection, , No., , About, , 18 years, inland, , plus high airborne salt levels), severe, iv), , or organic/paint, , /, , (2), , iii), , coatings, , Guide for Steel Work Application — Desired Life of Coating, System in Different Environments, , Atmospheric Condition/, Environmental Classification, , (1), , the electrode potential,, , 15.2.4.1 In the case of mild exposure, a coat of primer, after removal of any loose mill scale may be adequate., As the exposure condition becomes more critical, more, elaborate surface preparations and coatings become, necessary., In case of extreme, environmental, classification,, protection shall be as per specialist, literature. Table 29 gives guidance to protection of, steelwork for different desired lives., , The methods of corrosion protection are governed by, actual environmental conditions as specified in IS 9077, , No., , Controlling, , methods, , 15.2.4 Su~ace Protection, , 15.2.3 Corrosion Protection Methods, , Table 29 (a) Protection, , a), , protection, , —, , Blast clean, 2 pack zinc-rich, epoxy, 20 pm, 2 pack zinc-rich, epoxy, 20 pm, , Blast clean, Gkt blast, 2 pack zinc-rich, —, epoxy, 20p, 2 pack zinc-rich Sprayed zinc or, sprayed, epoxy, 25 pm, aluminium, , Blast clean, Ethyl zinc, silicate, 20 Urn, Ethyl zinc, silicate, 60 pm, , —, , 2 pack epoxy, micaceous iron, oxide, , Sealer, , Chlorinated, rubber alkyd,, 35pm, , ., , 2 pack epoxy, micaceous iron, oxide, 85 Urn, , Sealer, , Blast clean, , Hot dip, galvanized,, 85pm, , High-build zinc, phosphate, 25 pm, , —, , 104, , —

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IS 800:2007, Table 29 (b) (ii) Protection, , sl, , Guide for Steel Work Application — Specification, System (Site Applied Treatments), (Clause 15.2.4.1), , for Different, , Coating System, , Protection, , No., , -, , /, , (1), , O, , (2), , Surface, , 1, , 2, , 3, , 4, , 5, , (3), , (4), , (5), , (6), , (7), , As necessary, , As necessary, , Touch in, , Touch in, , preparation, , ii), , Primer, , iii), , Intermediate, coat, , Coating, , No site, treatment, —, , As necessary, , —, , Touchtn, , Modified, Alkyd, Micaceous, iron oxide,, , —, , 6, (8), , lQo site, , As necessary, , treatment, —, , Touchin, , —, , High-build, micaceousiron, oxide, Chlorinated, rubber, , 50 ~m, , Micaceous,, iv), , TOPcoat, , High-build, Alkyd finish,, 60~m, , Modified, Alkyd, Micaceous, iron oxide,, 50 pm, , 15.2.4.2 Steel surfaces shall be provided with at least, one coat of primer immediately, after its surface, preparation such as by sand blasting to remove all mill, scale and rust and to expose the steel., 15.2.4.3 Steel without protective coating shall not be, stored for long duration in out door environment., 15.2.4.4 Surfaces to transfer forces by friction as in, HSFG connections shall not be painted. However it, shall be ensured that moisture is not trapped on such, surfaces after pretensioning, of bolts by proper, protective measures., , —, , —, , High-build, chlorinated, rubber, , 75 pm, H@t-build iron, oxide Chlorinated, rubber, 75 ~m, , SECTION 16, FIRE RESISTANCE, 16.1 Requirements, The requirements shall apply to steel building elements, designed to exhibit a required fire-resistance, level, (FRL) as per the relevant specifications., 16.1.1 For protected steel members and connections,, the thickness of protection material (hi) shall be greater, than or equal to that required to give a period of, structural adequacy (PSA) greater than or equal to the, required FRL., , 15.2.4.5 Members to be assembled by welding shall, not be pre-painted at regions adjacent to the location, of such welds. However, after welding, appropriate, protective coatings shall be applied in the region, as, required by the exposure conditions. If the contact, surfaces cannot be properly protected against ingress, of moisture by surface coating, they maybe completely, sealed by appropriate welds., , 16.1.2 For unprotected steel members and connections,, the exposed surface area to mass ratio (k,~) shall be, less than or equal to that required to give a PSA equal, to the required FRL., 16.2 Fire Resistance, , Level, , The required FRL shall be as prescribed in IS 1641,, IS 1642 and IS 1643, as appropriate or in building, specifications or as required by the user or the city, ordinance. The FRL specified in terms of the duration, (in minutes) of standard fire load without collapse, depends upon:, , 15.2.4.6 Pre-painted, members shall be protected, against abrasion of the coating during transportation,, handling and erection., 15.2.5 Special Steels, Steels with special alloying elements and production, process to obtain better corrosion resistance may be, used as per specialist literature., , 105, , a), , the purpose for which structure is used, and, , b), , the time taken to evacuate in case of fire.

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IS 800:2007, 16.3 Period of Structural, , Adequacy, , 1.2, , (PSA), , 16.3.1 The calculation of PSA involves:, a), , b), , c), , CURVE 1: YEILDSTRESS RATIO, CURVE 2: MODULUSOF, , 1.0, , Calculation of the strength of the element as, a function of temperature of the element and, the determination of limiting temperature;, , ELASTICITY, RATIO, I, I, , 0.8, 0.6, , I, , Calculation of the thermal response of the, element, that is calculation of the variation of, the temperature of the element or the parts of, the element with time, when exposed to fire;, and, , 0.4, , L, , I, I, , 0.2, , ‘-, , I, 0, , Determination, of PSA at which, the, temperature of the element or parts of the, element reaches the limiting temperature., , I, , ’215, , 0, , 200, , 400, , 600, , 800, , T, , 1000 1200, , STEELTEMPERATURE, (T)“C, FIG. 24 VARIATION OF MECHANICAL PROPERTIES OF, , 16.3.2 Determination of Period of Structural Adequacy, , STEEL WITH TEMPERATURE, , The period of structural adequacy (PSA) shall be, determined using one of the following methods:, a), , For temperature less than 215°C no reduction, yield stress need to be considered., , By calculation:, Variation, Temperature, , of Modulus, , 16.4.2, 1), , 2), , b), c), , in the, , determining the limiting temperature of, the steel (T,) in accordance with 16.5 ;, and, determining the PSA as the time (in rein), from the start of the test to the time at, which the limiting steel temperature (t), is attained, in accordance with 16.6 for, protected, members, and 16.7 for, unprotected members., , By direct application, of a single, accordance with 16.8; or, , 16.4 Variation of Mechanical, with Temperature, , Properties, , E(T), —, , when, , =, , of Steel, , 905-T, —, , <10, , 905, , – -, , of mild steels, , fy(20), , T = temperature, This relationship, , of steel, and, , )1., , 600”C, , 690 l-~, () 1000, , T-53.5, , =, , T S, , modulus, and, , This relationship, , 1 OOO”C, , of elasticity, , of steel at, , T “C,, , of steel at 2(YC, , is shown by curve 2 in Fig. 24., , 16.4.3 For special steel with higher temperature, resistance, such as TMCP steels, the manufacturer’s, recommendation, shall be used to obtain the variation, of yield strength and modulus of elasticity of steel with, temperature., , = yield stress of steel at T°C,, = yield stress, temperature),, , [, , T, , —, ( 1100, , E (20) = modulus of elasticity, (room temperature)., , where, fy(T), , T S, , 600”C <, E (7), , The influence of temperature on the yield stress of steel, , fy(T), —=, f, (20), , 20001n, , O“C <, , when, , shall be taken as follows for structures, and high strength low alloy steels:, , T, , 1.0+, , =, , E(20), , I, , 16.4.1 Variation of Yield Stress with Temperature, , with, , The influence of temperature, on the modulus of, elasticity shall be taken as follows for structures of mild, steels and high strength low alloy steels:, , test in, , By calculation of the temperature of the steel, member by using a rational, method of, analysis confirmed by test data or by methods, available in specialist literature., , of Elasticity, , at 20°C (room, , 16.5 Limiting Steel Temperature, , of the steel in “C., , The limiting steel temperature (Tl) in degree Celsius, in the case of ordinary steels, shall be calculated as, follows:, , is shown by Curve 1 in Fig. 24., , 106

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.,.,.,..,., ,,, , ———, , IS 800:2007, T]=, , 905-690 rf, , t=kO+klhi +k2;, , where, , +k~T+kahiT+k#+kb~, sm, , r~ = ratio of the design action on the member, , kOto k~ = regression coefficients, (see 16.6.2.2.);, , R~,I?u = design strength and ultimate strength of, , l% = ptiial, The design, following:, , action, , hi = thickness, , temperature, , fire shall, , T, , consider, , of fire protection, , material,, , =, , the, , steel temperature,, in degrees, as, obtained, from, test, in 16.6.1, T > 250” C; and, , celsius, given, , k,~ = exposed surface area to mass ratio, in, , a), , Reduced bond likely under tire, and, , b), , Effects of restraint, elements during fire., , to expansion, , 103 mm2/kg., of the, , 16.6.2.2 In lieu of test results, the values for coefficients, in Table 30 may be used in the equation 16.6.2.1 when, the test satisfies the conditions specified in 16.6.2.3., , Limiting steel temperature for special steels may be, appropriately, calculated, using, the thermal, characteristics, of the material obtained from the, supplier of the steel., 16.6 Temperature, Members, , from test data, , in mm;, , safety factor for strength., under, , sm, , t = time from the start of the test, in rein;, , under tire to the design capacity of the, member, (R~ = Ru/y~), at room, temperature,, the member, at room, respectively, and, , sm, , where, , Increase, , Table 30 Regression, , with Time in Protected, , 16.6.1 The time (t) at which the limiting temperature, by calculation on, the basis of a suitable series of fire tests in accordance, with 16.6.2 or from the results of a single test in, accordance with 16.6.3., , (Ti) is attained shall be determined, , Coefficients,, , k, , kO, , k,, , kz, , k3, , k4, , k5, , k6, , (1), , (2), , (3), , (4), , (5), , (6), , (7), , -25.90, , 1.698, , -13.71, , 0.0300, , 0.0005, , 0.5144, , 6.633, , 16.6.2.3 Limitations, regression analysis, , and conditions, , Test data to be utilized in accordance, shall satisfy the following:, , on use of, , with 16.6.2.1,, , 16.6.1.1 For beams and for all members with a foursided fire exposure condition, the limiting temperature, (Tl) shall be taken as the average of all of the, temperatures measured at the thermocouple locations, on all sides., , a), , Steel members shall be protected with board,, sprayed blanket or similar insulation materials, having a dry density less than 1000 kg/m3;, , b), , All tests shall incorporate, protection system;, , 16.6.1.2 For columns with a three-sided fire exposure, condition, the limiting temperature (7’1)shall be taken, as the average of the temperatures measured at the, thermocouple locations on the face farthest from the, wall. Alternatively, the temperatures from members, with a four-sided fire exposure condition and having, the same surface area to mass ratio may be used., , c), , All members shall have the same fire exposure, condition;, , d), , Test series shall include at least nine tests;, , e), , Test series may include prototypes which have, not been loaded provided that stackability has, been demonstrated; and, , f), , All members subject to a three-sided fire, exposure condition shall be within a group in, accordance with 16.9., , 16.6.2 Temperature Based on Test Series, Calculation of the variation of steel temperature with, time shall be by interpolation of the results of a series, of fire tests using the regression analysis equation, specified in 16.6.2.1, subject to the limitations and, conditions of 16.6.2.3., , the same fire, , The regression equation obtained for one tire protection, system may be applied to another system using the, same fire protection material and the same fire exposure, condition, provided, that stackability, has been, demonstrated for the second system., , 16.6.2.1 Regression analysis, , A regression equation obtained using prototypes with, a four-sided fire exposure condition maybe applied to, a member with a three-sided fire exposure condition, provided that stackability has been demonstrated for, the three-sided case., , The relationship between temperature (T) and time (t), for a series of tests on a group shall be calculated by, least-square regression as follows:, , 107

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1S 800:2007, 16.6.3 Temperature Based on Single Test, , a), , Conditions,, , The variation of steel temperature with time measured, in a standard fire test maybe used without modification, provided:, , b), , Conditions of support are the same as the, prototype, and the restraints, are not less, favorable, than those of the prototype, and, , c), , Ratio of the design load for fire to the design, capacity of the member is less than or equal, to that of the prototype., , a), , Fire protection, prototype;, , b), , Fire exposure, prototype;, , c), , Fire protection material thickness is equal to, or greater than that of the prototype;, , d), , Surface area to mass ratio is equal to or less, than that of the prototype; and, , e), , Where the prototype has been submitted to a, standard fire test in an unloaded condition,, stackability has been separately demonstrated., , system, , is the same as the, , condition, , is the same as the, 16.9 Three-Sided, , a), , b), , Exposed surface area to mass ratio;, , c), , Insulation, thickness;, , d), , Moisture content of the insulation, , type,, and, , thermal, , properties, , highest in group, , <1.25,, , 2), , and, , with, , material., Time, , in, b), , b), , Four-sided, , t = 4.7, , c), , fire exposure condition, , t=5.2+0.022, , 1, , T+, , o.433q, k sm, , -, , 3, , k sm, , steel temperature,, s T ~ 75t)°C, and, , in “C, 500 “C, , largest in group, smallest in group, , IUb voids shall either be:, 1), , all open; or, , 2), , all blocked as shown in Fig. 25B., , Concrete slabs may incorporate, steel deck formwork., , permanent, , 16.10.2 Web Penetrations, , k,~ = exposed, , surface, area to mass, ratio, 2x103 mm2/kg S k,m S 35, x103 mm2/kg., , The thickness of tire protection material at and adjacent, to web penetrations, shall be the greatest of that, required, when:, , For temperatures below 500°C, linear interpolation, shall be used, based on the time at 500”C and an initial, temperature of 20”C at tequals O., 16.8 Determination, , Effective thickness (h,):, , Connections, shall be protected with the maximum, thickness of fire protection material required for any, of the members framing into the connection, to, achieve their respective fire-resistance, levels. This, thickness shall be maintained, over all connection, components, including bolt heads, welds and splice, plates., , = time from the start of the test, in rein,, , T=, , and, , 16.10.1 Connections, , where, t, , lowest in group, , 16.10 Special Considerations, , fire exposure condition, , +0.0263T+, , density:, , where the effective thickness (h.) is equal to, the cross-sectional area excluding voids per, unit width, as shown in Fig. 25A., , The time (t)at which the limiting temperature (Tl) is, attained shall be calculated, using the following, equations:, Three-sided, , Concrete, , SI.25., , 16.7 Temperature, Increase, Unprotected Members, , a), , Condition, , The characteristics of the members of a group, as given below, shall not vary from one, another by more than, 1), , Test, Specimen type, loading, configuration;, , Fire Exposure, , Members subject to a three-sided, fire exposure, condition shall be considered in separate groups unless, the following conditions are satisfied:, , 16.6.4 Parameters of Importance in the Standard Fire, , a), , specified in 16.6.3 are satisfied,, , a), , area above the penetration is considered as a, three-sided, fire exposure condition (k,~l), (see Fig. 26),, , b), , area below the penetration, four-sided, fire exposure, (see Fig. 26), and, , of PSA from a Single Test, , The period of structural adequacy (PSA) determined, from a single test maybe applied without modification, provided:, 108, , is considered as a, (k,~2), condition

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IS 800:2007, c), , 16.11 Fire Resistance, , section as a whole is considered as a threesided, fire, exposure, condition, (k,~), (see Fig. 26)., , Rating, , The fire resistance, rating of various building, components such as walls, columns, beams, and floors, are given in Table 31 and Table 32. Fire damage, assessment, of various structural, elements of the, building and adequacy of the structural repairs can be, done by the fire resistance rating for encased steel, column and beam (Table 31 and Table 32)., , This thickness shall be applied over the full beam depth, and shall extend on each side of the penetration for a, distance at least equal to the beam depth and not less, than 300 mm,, , t, , h-%lkr-E3ki’-J, &, , i%, , -, , .>, , 25A Effective Thickness, , ~RETE, , }, , VOID BLOCKED WITH, FIRE PROTECTION, MATERIAL, , SLAB, , /’, , 4, STEEL BEAM, FIRE PROTECTION, MATERIAL, , CROSS SECTION, , SIDE VIEW, , 25B Blocking of Rib Voids, FIG. 25 THREE SIDEDFIRE EXPOSURECONDITION REQUIREMENTS, , w, , Side View of Beam with Web Penetration, . . .. ...... #...:,., -., .,., . . . . ., , .. . . . .. ., k smf, ii, , SECTION A-A, , SECTION, , FIG. 26 WEB PENETRATION, , 109, , B-B

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IS 800:2007, Table 31 Encased Steel Columns, 203 mm x 203 mm, (Protection Applied on Four Sides), (Clause 16.1 1), SI, , Nature of Construction, , and Materials, , Minimum Dimensions, , No., , (1), , (2), , O, , Hollow protection (without an air cavitv over the flanges):, Metal lathing with trowelled ligh~weightaggreg;te’gypsum, O, plaster ‘), b), Plasterboard with 1.6 mm wire binding at 100 mm pitch,, finished with lightweight aggregate gypsum plaster less, than the thickness specified:, I) 9.5 mm plaster board, 2) 19 mm plaster board, Asbestos insulating boards, thickness of board:, c), 1) Single thickness of board, with 6 mm cover fillets at, transverse joints, 2) Two layers, of total thickness, Solid bricks Of clay, composition or sand lime, reinforced, d), in every horizontal joint, unplastered, Aerated concrete blocks, e), Solid blocks of lightweight concrete bellow protection, f-), (with an air cavity over the flanges), Asbestos, insulating, board screwed to 25 mm asbestos battens, Solid protections, Concrete, not leaner than 1:2:4 mix (unplastered):, a), 1) Concrete not assumed to be load bearing, reinforced 2), 2) Concrete assumed to be load bearing, b), Lightweight concrete, not leaner than 1:2:4 mix (unplastered) concrete not assumed to be load bearing, reinforced 2), , ii), , iii), , Excluding Any Fhrish, for a Fire, Resistance of, mm, , lh, (3), , 1 fih, , 2h, , 3h, , 4 h’, , (4), , (5), , (6), , (7), , 13, , 15, , 20, , 32, , 10, 10, , 15, 13, , 20, , —, —, , —, , 19, , 2.5, , —, , —, , —, , 50, , 50, , 50, , 38, 75, , 60, , 60, , 60, , —, , 50, , 50, , 50, , 60, , –, , 50, 100, , 75, , —, , 19, , 25, , 25, , 25, , 50, 25, , 50, 25, , 50, 25, , 50, ’75, 25, , 75, 75, 25, , ‘)So fixed or designed. as to allow full Penetration for mechanical bond., ‘1Reinforcement ~hallconsist Ofsteel ilnd]ng wire not less than 2.3 mm diameter, or a steel mesh weighing not lesstharrO.sk@2. ln, concrete protection, the spacing of the reinforcement shall not exceed 200 mm in any direction., , SECTION 17, FABRICATION, AND ERECTION, , connecting steel to steel should preferably be not, greater than 2,0 mm at each end. The erection clearance, at ends of beams without web cleats should be not more, than 3 mm at each end. Where for practical reasons,, greater clearance is necessary, suitably designed seating, should be provided., , 1’7.1 General, Tolerances for fabrication of steel structures shall, conform to IS 7215. Tolerances for erection of steel, structures shall conform to IS 12843. For general, guidance on fabrication by welding, reference maybe, made to IS 9595., 17.2 Fabrication, , 17.2.2.1 In bearing type of connections, the holes may, be made not more than 1.5 mm greater than the, diameter of the bolts in case of bolts of diameter less, than 25 mm and not more than 2 mm in case of bolts, of diameter more than 25 mm, unless otherwise, specified by the engineer. The hole diameter in base, plates shall not exceed the anchor bolt diameter by, more than 6 mm., , Procedures, , 17.2.1 Straightening, Material shall be straightened or formed to the specified, configuration, by methods that will not reduce the, properties of the material below the values used in, design. Local application of pressure at room or at, elevated temperature or other thermal means may be, used for straightening, provided the above is satisfied., , 17.2.2.2 In friction type of connection clearance may, be maintained, unless specified otherwise in the design, document., 17.2.3 Cutting, , 17.2.2 Clearances, The erection clearance, , Cutting shall be effected by sawing, shearing, cropping,, machining, or thermal cutting process. Shearing,, , for cleated ends of members., 110

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_,.,_, .., _., , IS 800:2007, Table 32 Encased Steel Beams, 406 mm x 176 mm, (Protection Applied on Three Sides), (Clause 16.11 ), S1, , Nature of Construction, , Minimum Thickness of Protection for a Fire, Resistance of, , and Materials, , No., , mm, A, , /, (2), , (1), , Hollow protection (without an air cavity beneath the lower flanges):, a) Metal lathing with trowelled lightweight aggregate gypsum plaster’), b) Plasterboard with 1.6 mm wire binding at 100 mm pitch, finished with, lightweight aggregate gypsum plaster less than the thickness specitiedz), 1) 9.5 mm plaster board, 2), 19 mm plaster board, c) Asbestos insulating boards, thickness of board, 1) Singlettdcknessof board,with 6 mm coverfilletsat transversejoints, 2) Two layers, of total thickness, protection(with an air cavitybelowthe lowerflange), ii) HO11OW, @ Asbestosinsulatingboard screwed to 25 mm asbestos battens, iii) Solid protections, a) Concrete, not leaner than 1:2:4 mix (unpkistered):, 1) Concrete not assumed to be load bearing, reinforced 3), Concrete assumed to be load bearing, 2), , 1/2 h, , Ih, , lfih, , 2h, , 3h, , ?, 4h, , (3), , (4), , (5), , (6), , (7), , (8), , 13, , 13, , 15, , 20, , 25, , 10, , 10, , 15, , —, , —, , 10, , 10, , 13, , 20, , —, —, , —, —, , 19, —, , 25, —, , 9, , 12, , 25, 50, , 25, 50, , 25, 50, , 25, 50, , 50, , 75, , 75, , 25, , 25, , 25, , 25, , 40, , 60, , i), , b), , Lightweightconcrete,not leanerthan 1:2:4mix (unplastered)4), , —, , —, , 38, , —, , —, 50, —, , 75, , 1)so fixedor designed,as to allow full penetrationfor mechanicalbond., ‘)Wherewire bindingc~not be used, expert adviceshouldbe soughtregarding akemative methods OfSupportto enablethe loweredges, of the plasterboard to be fixed together and to the lower flange, and for the top edge of the plasterboard to be held in position., , 3) Reinforcement, , shall consist of s&el binding wire not less than 2.3 mm, , a steel mesh weighing not less than 0.5 k~mz. In, mm in any direction., , in diameter, or, , concrete protection, the spacing of the reinforcement shall not exceed 200, 4) concrete, not assumed to be load bearing, reinforced., , by machining, so that all metal that has been hardened, by flame is removed. Hand flame cutting may be, permitted only subject to the approval of the inspecting, authority., , cropping and gas cutting shall be clean, reasonably, square, and free from any distortion., Should the, inspector find it necessary, the edges shall be ground, after cutting. Planning or finishing of sheared or gascut edges of plates or shapes shall not be required,, unless specially noted on drawing or included in, stipulated edge preparation, for welding or when, specifically required in the following section., , Except where the material is subsequently joined by, welding, no load shall be transmitted through a gas, cut surface., Thermally cut free edges, which shall be subject to, calculated static tensile stress shall be free from round, bottom gouges greater than 5 mm deep. Gouges greater, than 5 mm deep and notches shall be removed by, grinding., , Re-entrant comers shall be free from notches and shall, have largest practical radii with a minimum radius of, 15 mm., 17.2.3.1 Shearing, , 17.2.4 Holing, , Shearing of items over 16 mm thick to be galvanized, and subject to tensile force or bending moment shall, not be carried out, unless the item is stress relieved, subsequently., , 17.2.4.1 Holes through more than one thickness of, material for members, such as compound stanchion and, girder flanges, shall be where possible, drilled after the, members are assembled and tightly clamped or bolted, together. Around hole for a bolt shall either be machine, flame cut, or drilled full size, or sub-punched 3 mm, undersize and reamed to size or punched full size., , The use of sheared edges in the tension area shall be, avoided in location subject to plastic hinge rotation at, factored loading., 17.2.3.2 Thermal cutting, , Hand flame cutting of a bolt hole shall not be permitted, except as a site rectification, measure for holes in, column base plates., , Gas cutting of high tensile steel by mechanically, controlled torch may be permitted, provided special, care is taken to leave sufficient metal to be removed, 111

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IS 800:2007, 17.2.4.2 Punching, , 17.3 Assembly, , A punched hole shall be permitted only in ‘material, whose yield stress WY)does not exceed 360 MPa and, where thickness does not exceed (5 600/~Y) mm. In, cyclically loaded details, punching shall be avoided in, plates with thickness greater than 12 mm., , All parts of bolted members shall be pinned or bolted, and rigidly held together during assembly., The component parts shall be assembled and aligned, in such a manner that they are neither twisted nor, otherwise damaged, and shall’ be so prepared that the, specified camber, if any, is provided., , For greater thickness and cyclically loaded details,, holes shall be either drilled from the solid or subpunched or sub-drilled and reamed., , 17.3.1 Holes in Assembly, When holes are drilled in one operation through two, or more separable parts, these parts, when so specified, by the engineer, shall be separated after drilling and, the burrs removed., , The die for all sub-punched holes or the drill for all, sub-drilled holes shall be at least 3 mm smaller than, the required diameter of finished hole., 17.2.4.3 Oversize holes, , Matching holes for rivets and black bolts shall register, with each other so that a gauge of 1.5 mm or 2.0 mm, (as the case may be, depending on whether the diameter, of the rivet or bolt is less than or more than 25 mm), less in diameter than the diameter of the hole will pass, freely through the assembled members in the direction, at right angle to such members., , A special plate washer of minimum thickness 4 mm, shall be used under the nut, if the hole diameter is larger, than the bolt diameter by 3 mm or more., Oversize hole shall not exceed 1.25d or (d+8) mm in, diameter, were d is the nominal bolt diameter, in mm., A short slotted hole shall not exceed the appropriate, hole size in width and 1.33d in length. A long slotted, hole shall not exceed the appropriate hole size in width, and 2.5d in length. If the slot length is larger than those, specified, shear transfer in the direction of slot is not, admissible even in friction type of connection., , Drilling done during assembly to align holes shall not, distort, , the metal or enlarge, , the holes., , Holes in adjacent part shall match sufficiently well to, permit easy entry of bolts. If necessary, holes except, oversize or slotted holes maybe enlarged to admit bolts,, by moderate amount of reaming., , Slotted holes shall be punched either in one operation, or else formed by punching or drilling two round holes, apart and completed by high quality mechanically, controlled flame cutting and dressing to ensure that, bolt can freely travel the full length of the slot., , 17.3.2 Thread Length, When design is based on bobs with unthreaded shanks, in the shear plane, appropriate, measures shall be, specified to ensure that, after allowing for tolerance,, neither the threads nor the thread run-out be in the shear, plane., , 17.2.4.4 Fitted bolt holes, Holes for turned and fitted bolts shall be drilled to a, diameter equal to the nominal diameter of the shank, or barrel subject to tolerance specified in IS 919 (Parts, 1 and 2). Preferably, parts to be connected with close, tolerance or barrel bolts shall be firmly held together, by tacking bolts or clamps and the holes drilled through, all the thicknesses at one operation and subsequently, reamed to size. All holes not drilled through all, thicknesses atone operation shall be drilled to a smaller, size and reamed out after assembly. Where this is not, practicable,, the parts shall be drilled and reamed, separately through hard bushed steel jigs., , The length of bolt shall be such that at least one clear, thread shows above the nut and at least one thread plus, the thread run out is clear beneath the nut after, tightening. One washer shall be provided under the, rotated part., 17.3.3 Assembly Subjected, , to Vibration, , When non-preloaded, bolts are used in a structure, subject to vibration, the nuts shall be secured by locking, devices or other mechanical, means. The nuts of, preloaded bolts may be assumed to be sufficiently, secured by the normal tightening procedure., , 17.2.4.5 Holes for rivets or bolts shall not be formed, generally by gas cutting process. However, advanced, gas cutting processes such as plasma cutting may be, used to make holes in statically loaded members only., In cyclically loaded members subjected to tensile, stresses which are vulnerable under fatigue, gas cutting, shall not be used unless subsequent reaming is done to, remove the material in the heat affected zone around, the hole., , 17.3.4 Washers, Washers are not normally required on non-preloaded, bolts, unless specified otherwise. Tapered washers shall, be used where the surface is inclined at more than 3“to, a plane perpendicular to the bolt axis., Hardened washer shall be used for preloaded bolts or, the nut, whichever is to be rotated., 112

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IS 800:2007, and that the final dimensions, tolerances., , All material within the grip of the bolt shall be steel, and no compressible material shall be permitted in the, grip., , 17.7 Machining, 17.4 Riveting, , of Butts, Caps and Bases, , 17.7.1 Column splices and butt joints of struts and, compression members, depending on contact for stress, transmission, shall be accurately machined and closebutted over the whole section with a clearance not, exceeding 0.2 mm locally, at any place. Sum of all, such clearance shall not be more than 30 percent of, the contact area for stress transmission. In column caps, and bases, the ends of shafts together with the attached, gussets, angles, channels, etc; after connecting together, should be accurately, machined so that clearance, between the contact surfaces shall not exceed 2 mm, locally, subject further to the condition that sum total, of all such clearance shall not exceed 30 percent of the, total contact area for stress transmission. Care should, be taken that these gussets, connecting, angles or, channels are fixed with such accuracy that they are, not reduced in thickness by machining by more than, 2.0 mm,, , 17.4.1 Rivets shall be heated uniformly throughout, their length, without burning or excessive scaling, and, shall be of sufficient length to provide a head of, standard dimensions., These shall, when driven,, completely fill the holes and, if countersunk,, the, countersinking, shall be fully filled by the rivet. lf, required, any protrusion of the countersunk head shall, be dressed off ftush., 17.4.2 Riveted member shall have all parts firmly, drawn and held together before and during riveting,, and special care shall be taken in this respect for all, single-riveted, connections., For multiple riveted, connections, a service bolt shall be provided in every, third or fourth hole., 17.4.3 Wherever practicable, machine riveting shall be, carried out by using machines of the steady pressure, type., , 17.7.2 Where sufficient, gussets and rivets or welds are, provided to transmit the entire loading (see Section 4),, the column ends need not be machined., , 17.4.4 All loose, burned or otherwise defective rivets, shall be cut out and replaced before the structure is, loaded, and special care shall be taken to inspect all, single riveted connections., , 17.7.3 Slab Bases and Caps, Slab bases and slab caps, except when cut from material, with true surfaces, shall be accurately machined over, the bearing surfaces and shall be in effective contact, with the end of the stanchion, the bearing face which, is to be grouted to fit tightly at both top and bottom,, unless welds are provided to transmit the entire column, face., , 17.4.5 Special care shall be taken in heating and driving, long rivets., 17.5 Bolting, 17.5.1 In all cases where the full bearing area of the, bolt is to be developed, the bolt shall be provided with, a washer of sufficient thickness under the nut to avoid, any threaded portion of the bolt being within the, thickness or the parts bolted together, unless accounted, for in design., 17.5.2 Pre-tensioned, tension (the proof, calibmted method., , are within appropriate, , 17.7.4 To Facilitate grouting, sufficient gap shall be left, between the base plates and top of pedestal and holes, shall be provided where necessary in stanchion bases, for the escape of air., , bolts shall be subjected to initial, stress) by an appropriate, pre-, , 17.8 Painting, , 17.6 Welding, , 17.8.1 Painting shall be done in accordance, IS 1477 (Parts 1 and 2)., , with, , 17.6.1 Welding shall be in accordance with IS 816,, IS 819, IS 1024, IS 1261, IS 1323 and IS 9595, as, appropriate., , 17.8.2 All surfaces, which are to be painted, oiled or, otherwise treated, shall be dry and thoroughly cleaned, to remove all loose scale and loose rust., , 17.6.2 For welding of any particular type of joint,, welders shall give evidence acceptable to the purchaser, of having satisfactorily completed appropriate tests as, prescribed in IS 817, IS 1393, IS 7307 (Part 1), IS 7310, (Part 1) andIS7318, (Part 1), as relevant., , 17.8.3 Shop contzact surfaces need not be painted unless, specified. If so specified, they shall be brought together, while the paint is still wet., 17.8.4 Surfaces not in contact, but inaccessible after, shop assembly,, shall receive tbe full specified, protective treatment before assembly. This does not, apply to the interior of sealed hollow sectiorf$., , 17.6.3 Assembly and welding shall be carried out in, such a way to minimize distortion and residuat stress, , 113

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IS 800:2007, 17.8.5 Chequered plates shall be painted but the details, of painting shall be specified by the purchaser., , fabrication is being undertaken, provisions of this standard., , 17.8.6 In case of surfaces to be welded, the steel shall, not be painted or metal coated within a suitable distance, of any edge to be welded, if the paint specified or the, metal coating is likely to be harmful to welders or, impair the quality of the welds., , 17.12.2 Unless specified otherwise, inspection shall, be made at the place of manufacture prior to dispatch, and shall be conducted, so as not to interfere, unnecessarily with the operation of the work., , in concrete, , 17.12.4 Should any structure or part of a structure be, found not to comply with any of the provisions of this, standard, it shall be liable to rejection. No structure or, part of the structure, once rejected shall be resubmitted, for test, except in cases where the purchaser or his, authorized, representative, considers, the defect as, rectifiable., , shall not be, , 17.8.9 Contact surface in friction type connection shall, not be painted in advance., 17.9 Marking, Each piece of steel work shall be distinctly marked, before dispatch, in accordance with a marking diagram, and shall bear such other marks as will facilitate, erection,, , 17.12,5 Defects, which may appear during fabrication,, shall be made good with the consent of and according, to the procedure laid down by the inspecting authority., 17.12.6 All gauges and templates necessary to satisfy, the inspection, authority shall be supplied by the, manufacturer. The inspecting authority may, at his, discretion,, check the test results obtained at the, manufacturer’s works by independent testing at outside, laboratory, and should the material so tested be found, to be unsatisfactory, the cost of such tests shall be borne, by the manufacturer, and if found satisfactory, the cost, shall be borne by the purchaser., , 17.10 Shop Erection, 17.10.1 The steel work shall be temporarily, shop, erected complete or as arranged with the inspection, agency so that accuracy of fit may be checked before, dispatch. The parts shall be shop assembled with, sufficient numbers of parallel drifts to bring and keep, the parts in place., 17.10.2 In the case of parts drilled or punched, through, steel jigs with bushes resulting in all similar parts being, interchangeable, the steelwork maybe shop erected in, such position as arranged with the inspection agency., , 17.13 Site Erection, 17.13.1 Plant and Equipment, The suitability and capacity of all plant and equipment, used for erection shall be to the satisfaction of the, engineer., , 17.10.3 In case of shop fabrication using numerically, controlled, machine data generated, by computer, software (like CAD), the shop erection may be, dispensed with at the discretion of the inspector., , 17.13.2 Storing and Handling, All structural steel should be so stored and handled at, the site that the members are not subjected to excessive, stresses and damage by corrosion due to exposure to, environment., , 17.11 Packing, All projecting plates or bars and all ends of members, at joints shall be stiffened, all straight bars and plates, shall be bundled, all screwed ends and machined, surfaces shall be suitably packed and all rivets, bolts,, nuts, washers and small and loose parts shall be packed, separately, in cases, so as to prevent damage or, distortion during transit., 17.12 Inspection, , with the, , 17.12.3 The manufacturer shall guarantee compliance, with the provisions of this standard, if required to do, so by the purchaser., , 17.8.7 Welds and adjacent parent metal shall not be, painted prior to de-slagging, inspection and approval., 17.8.8 Parts to be encased, painted or oiled., , in accordance, , 17.13.3 Setting Out, The positioning and Ievelling of all steelwork, the, plumbing of stanchions and the placing of every part, of the structure with accuracy shall be in accordance, with the approved drawings and to the satisfaction of, the engineer in accordance with the deviation permitted, below., , and Testing, , 17.12.1 The inspecting authority shall have free access, at all reasonable, times to those parts of the, manufacturer’s works which are concerned with the, fabrication of the steelwork and shall be afforded all, reasonable facilities for satisfying himself that the, , 17.13.3.1 Erection tolerances, Unloaded steel structure, as erected, shall satisfy the, criteria specified in Table 33 within the specified, tolerance limits., 114

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IS 800:2007, tested wire rope slings of correct size. The devices, should be well maintained and operated by experienced, operators., , Each criterion given in the table shall be considered as, a separate requirement, to be satisfied independent of, any other tolerance criteria. The erection tolerances, specified in Table 33 apply to the following reference, points:, a), , Table 34 Straightness Tolerances Incorporated, Design Rules, (Clause 7.13.3.1), , For a column, the actual centre point of the, column at each floor level and at the base,, excluding any base-plate or cap-plate. The, level of the base plate on pedestal shall be so, as to avoid contact with soil and corrosive, environment; and, , b), , S1, , L%, , Tolerances, , (1), Deviation, between, , ii), , Permitted Deviation, , (1), , (2), , (3), , O, , Straightness of a column (or, other compression member), between points which will be, laterally restrained on, completion of erection, , 0.00 IL generally, and, 0.002L for members with, hollow cross-sections;, where, L is the length, between points which will, be laterally restrained, , Straightness of a, , 0.001L generally, and, 0.002L for members with, hollow cross-sections;, where, L is the length, between points which will, be laterally restrained, , ii), , After Erection, , Criterion, , Permitted Deviation, , (2), , (3), , compressionflangeof a, beam,relativeto the weak, axis, betweenpoints,which, will be laterallyrestrainedon, completionof erection., , No., , O, , Criterion, , No., , For a beam, the actual centre point of the top, surface at each end of the beam, excluding, any end-plate., , Table 33 Normal, , of, adjacent, , distance, , 5 mm, , columns, , 17.13.4.2 Oxygen and acetylene cylinders and their, hoses shall have distinctive colours. Cylinders should, be stored in upright position in well-ventilated rooms, or in open air, not exposed to flames, naked lights or, extreme heat and should also be in upright position, when they are being used. All gas cutting works shall, be done only by experienced, skilled gas cutters,, equipped with gloves, boots, aprons, goggles and good, cutting sets of approved make., , Inclinationof a columnin a 0.002h,, , multi-storey, building, between adjacent floor, levels, iii) Deviation of location of a, column in a multi-storey, building at any floor level, from a vertical line, through the intended, location of the column, base, iv) Inclination ofa column in, a single storey building,, (not supporting a crane, gantry) r)therthan a portal, frame, v) Inclination of the column, of a portal frame (not, supporting, , a crane, , gantry), , in, , where, h, is the storey height, , 0.0035 z M+”’, , where, z hb is the total height, from the base to the floor, level concerned and n is the, number of storeys from the, base to the floor level, concerned, 0.003 5h., where, h. is the height of the, column, , 17.13.4.3 While doing any welding work, it should be, ensured that the welding machine is earthed and the, welding cables are free from damage. The welder and, his assistant shall use a face shield or head shield with, a welding lens and clear cover glass and their hands,, legs and bodies shall be well protected by leather, gloves, shoes and aprons. Combustible materials should, be kept away from the sparks and globules of molten, metals generated in any arc welding. In case of welding, in a confined place, it should be provided with an, exhaust system to take care of the harmful gases, fumes, and dusts generated., , Mean: 0.002h,, Individual: O.OIOhC, where h, is the height of the, column, , The straightness tolerances specified in Table 34 have, been assumed in the derivation of the design stress for, the relevant type of member. Where the curvature, exceeds these values, the effect of additional curvature, on the design calculations shall be reviewed., , 17.13.4.4 In addition to precautions against all the, hazards mentioned above, erection workers shall also, be protected in the following manne~, , A tension member shall not deviate from its correct, position relative to the members, to which it is, connected by more than 3 mm along any setting axis., 17.13.4 Safety During Fabrication, , a), , All workers shall wear helmets and shall also, be provided with gloves and shoes. In addition, those working at heights shall use safety belts., , b), , All structures shall be so braced/guyed during, erection that there is no possibility of collapse, before erection work is completed., , c), , Warning signs such as ‘Danger’,, , and Erection, , 17.13.4.1 All steel materials including fabricated, structures, either at fabrication shop or at erection site,, shall be handled only by a worker skilled in such jobs;, where necessary with load tested lifting devices, having, , 115, , ‘Caution’,

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IS 800:2007, 17.14.3 Where the steel has received a metal coating, in the shop, this coating shall be completed on site so, as to be continuous over any welds and site rivets or, bolts, subject to the approval of the engineer. Painting, on site may complete protection. Bolts, which have, been galvanized or similarly treated, are exempted from, this requirement., , ’440 volts’, ‘Do not smoke’, ‘Look ahead’,, etc; should be displayed, at appropriate, places,, 17.13.4.5 For detailed safety precautions, erection, reference shall be made to IS 7205., , during, , 17.13.5 Field Connections, 17.13.5.1 Field riveting, , 17.14.4 Surface, which will be inaccessible after site, assembly, shall receive the full-specified protective, treatment before assembly., , Rivets driven at the site shall be heated and driven with, the same care as those driven in the shop., , 17.14.5 Site painting should not be done in frosty or, foggy weather, or when humidity is such as to cause, condensation on the surfaces to be painted., , 17.13.5.2 Field bolting, Field bolting shall be carried out with the same care as, required for shop bolting., , 17.15 Bedding Requirement, , 17.13.5.3 Fillet welding, , 17.15.1 Bedding shall be carried out with Portland, cement grout or mortar, as described under 17.15.4 or, fine cement concrete in accordance with IS 456., , Field assembly and welding shall be executed in, accordance with the requirements for shop fabrications, excepting such as manifestly apply to shop conditions, only. Where the steel has been delivered painted, the, paint shall be removed for a distance of at least 50 mm, on either side of the joint., 17.14, , 17.15.2 For multi-storeyed buildings, this operation, shall not be carried out until a sufficient number of, bottom lengths of stanchions have been properly lined,, leveled and plumbed and sufficient floor beams are in, position., , Painting After Erection, , 17.15.3 Whatever method is employed, the operation, shall not be carried out until the steelwork has been, finally Ievelled and plumbed, stanchion bases being, supported meanwhile by steel wedges or nuts; and, immediately before grouting, the space under the steel, shall be thoroughly cleaned., , 17.14.1 Before painting of such steel which is delivered, unpainted is commenced, all surfaces to be painted, shall be dry and thoroughly cleaned from all loose scale, and rust, as required, by the surface protection, specification., 17.14.2 The specified protective treatment shall be, ~ompleted after erection. All rivet and bolt heads and, the site welds after de-slagging, shall be cleaned., Damaged or deteriorated paint surfaces shall first be, made good with the same type of paint as the shop, coat. Where specified, surfaces which will be in contact, after site assembly, shall receive a coat of paint, (in addition to any shop priming) and shall be brought, together while the paint is still wet. No painting shall, be used on contact surfaces in the friction connection,, unless specified otherwise by the design document., , 17.15.4 Bedding of structure shall be carried out with, grout or mortar, which shall be of adequate strength, and shall completely fill the space to be grouted and, shall either be placed under pressure or by ramming, against fixed supports. The grouts or mortar used shall, be non’-shrinking variety., 17.16 Steelwork Tenders and Contracts, A few recommendations, general information., , 116, , are given in Annex G for

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IS 800:2007, ANNEX, , (Clause, LIST OF REFERRED, , 456:2000, 513:1994, 801:1975, , 808:1989, , 813:1986, 814:2004, , 816:1969, , 817, (Part 1): 1992, (Part 2): 1996, 819:1957, , 875, , (Part 1): 1987, , IS No., 1030:1998, , Plain and reinforced concrete —, Code of practice ~ourth revision), Cold-rolled low carbon steel sheets, and strips (fourth revision), Code of practice for use of coldformed light gauge steel structural, members, in general, building, construction first revision), Dimensions, for hot-rolled, steel, beam, column, channel and angle, sections (third revision), Scheme of symbols for welding, Covered electrodes for manual metat, arc welding of carbon and carbon, manganese steel — Specification, (sixth revision), Code of practice for use of metal arc, welding for general construction in, mild steel (first revision), Training of welders — Code of, practice:, Manual metal arc welding (second, revision), Oxyfuel welding (second revision), Code of practice for resistance spot, welding for light assemblies, in, mild steel, Code of practice for design loads, (other, than, earthquake), for, buildings and structures:, Dead loads – unit weights of building, materials, and stored materials, , 1079:1994, 1148:1982, , 1149:1982, 1261:1959, , 2):, 3):, 4):, 5):, , 1987, 1987, 1987, 1987, , 919, (Part 1): 1993/, ISO 286-1:1988, (Part 2) : 1993/, 1S0 286-2:1988, , 962:1989, 1024:1999, , 1278:, , 972, , 1323:, , 982, , Title, Carbon steel castings for general, engineering purposes ~fth revision), Hot rolled carbon steel sheets and, strips — Specification @fib revision), Specification for hot-rolled rivet bars, (up to 40 mm diameter) for structural, purposes (third revision), High tensile steel rivet bars for, structural purposes (third revision), Code of practice for seam welding, in mild steel, Specification for filler rods and wires, for gas welding (second revision), Code of practice for oxy-acetylene, welding for structural work in mild, steels (second, , 1363, (Part 1): 2002/, 1S0 4016:1999, (Part 2): 2002/, 1S04018:1999, (Part 3): 1992/, 1S0 4034:1986, 1364, , revision), , Hexagon head bolts, screws and nuts, of product grade C:, Hexagon head bolts (size range M5, to M64) ~ourth revision), Hexagon head screws (size range M5, to M64) ~ourth revision), Hexagon nuts (size range M5 to M64), , (third revision), , Hexagon head bolts, screws and nuts, of product grades A and B:, Hexagon head bolts (size range Ml.6, (Part 1): 2002/, to M64) ~ourth revision), 1s04014:1999, Hexagon head screws (size range, (Part 2): 2002/, Ml.6 to M64) (jourth revision), 1S04017:1999, Hexagon nuts, style 1 (size range, (Part 3): 2002/, M 1.6 to M64) (fourth revision) 1S04032:1999, Hexagon thin nuts (chamfered) (size, (Part 4): 2003/, range M 1.6 to M64) ($ourthrevision), 1s0 4035:1999, Hexagon thin nuts — Product grade B, (Part 5): 2002/, (unchamfered) (size range Ml.6 to, 1S0 4036:1999, M1O) ~ourth revision), Technical, supply conditions, for, 1367, threaded steel fasteners:, Generat requirements for bolts, screws, (Part 1): 2002/, and studs (third revision), 1S0 8992:1986, Tolerances for fasteners — Bolts,, (Part 2): 2002/, 1S04759-1 :2000 screws, studs and nuts — Product, grades A, B and C (third revision), (Part 3): 2002/, Mechanical properties of fasteners, 1S0 898-1:1999, made of carbon steel and alloy steel, — bolts, screws and studs ~ourth, , (second revision), (Part, (Part, (Part, (Part, , 1.1), , INDIAN STANDARDS, , Title, , IS No., , A, , Imposed loads (second revision), Wind loads (second revision), Snow loads (second revision), Special loads and load combinations, (second revision), 1S0 systems of limits and fits:, Bases of tolerance, deviations and fits, (second revision), Tables of standard tolerance grades, and limit deviations for holes and, shafts (/lrst revision), Code of practice for architectural and, building drawings (second revision), Code of practice for use of welding, in bridges and structures subject to, dynamic loading (second revision), , revision), 117

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IS 800:2007, , (Part 5) : 2002/, 1S0 898-5:1998, , (Part 6): 1994/, ISO 898-2:1992, (Part 7): 1980, , (Part 8) : 2002/, 1S0 2320:1997, (Part 9), Sec 1:1993/, 1S0 6157-1:1988, , Sec 2:19931, 1S0 6157-3:1988, (Part 10):2002/, 1S0 6157-2:1995, (Part 11):2002/, 1S0 4042:1999, (Part 12):1981, (Part 13):1983, (Part 14), Sec 1: 2002/, 1S0 3506-1:1997, , Mechanical properties of fasteners, made of carbon steel and alloy steei, — set screws and similar threaded, fasteners not under tensile stresses, (third revision), Mechanical properties and test methods, for nuts with specified proof loads, (third revision), Mechanical, properties, and test, methods for nuts without specified, proof loads (second revision), Prevailing torque type steel hexagon, nuts — Mechanical and performance, properties (third revision), Surface discontinuities, Bolts, screws and studs for general, , 1477, (Part 1): 1971, (Part 2): 1971, 1608: 2005/, ISO 6892:1998, 1641:1988, , 1642:1989, , 1643:1988, , 1875:1992, , 1387:1993, , 1893, (Part 1): 2002, , Phosphate, coatings, on threaded, fasteners (second revision), Hot dip galvanized, coatings, on, threaded fasteners (second revision), Mechanical properties of corrosionresistant stainless-steel fasteners,, Bolts, screws and studs (third revision), , 1929:1982, , 1990:1973, , 1395:1982, , Criteria for earthquake resistant design, of structures:, Part 1 General, provisions and buildings, Specification, for hot forged steel, rivets for hot closing (12 to 36 mm, diameter) tjirst revision), Steel rivet and stay bars for boilers, @rst, , revision), , 2002:1992, , Steel plates for pressure vessels for, intermediate and high temperature, service including boilers (second, , 2062:2006, , Hot rolled low, medium and high, tensile structural steel (sixth revision), Specification for cold forged solid, steel rivets for hot closing (6 to 16 mm, diameter) (first revision), 1.5 percent manganese steel castings, for general engineering, purpose, , revision), , 2155:1982, , system for fasteners, , (third revision), Inspection, sampling and acceptance, procedure (third revision), Packaging (third revision), Axial load fatigue testing of bolts,, screws and studs, Torsional test and minimum torques, for bolts and screws with nominal, diameters 1 mm to 10 mm, General requirements for the supply, of metallurgical, materials (second, , 2708:1993, , (third revision), 3039:1988, 3613:1974, , 3640:1982, , revision), 1393:1961, , Rolling and cutting tolerance for hot, rolled steel products ~ourth revision), Specification for carbon steel billets,, blooms, slabs and bars for forgings, , (fi$’hrevision), , revision), Electroplated coatings (tluki revision), , Designation, , Code of practice for painting of, ferrous metals in buildings:, Pre-treatment (/irst revision), Painting (first revision), Metallic materials —Tensile testing at, ambient temperatures (third revision), Code of. practice for fire safety of, buildings, (general):, General, principles, of fire grading, and, classification (first revision), Code of practice for fire safety of, buildings, (general):, Details of, construction (@ revision), Code of practice for fire safety of, buildings (general): Exposure hazard, , (jirst revision), 1852:1985, , application (third revision), Bolts, screws and studs for special, applications (third revision), Surface discontinuities — Nuts (third, , Nuts (third revision), Sec 2:20021, 1s0 3506-21997, Set screws and similar fasteners not, Sec 3:20021, 1S0 3506-3:1997 under tensile stress (third revision), (Part 16) : 2002/, 1S0 8991:1986, (Part 17) : 1996/, ISO 3269:1988, (Part 18) :1996, (Part 19) : 1997/, 1S0 3800:1993, (Part 20) : 1996/, 1S0 898-7:1992, , Title, , IS No., , Title, , IS No., , Structural steel for construction of, hulls of ships (second revision), Acceptance, tests for wire flux, combination, for submerged, arc, welding (first revision), Specification for hexagon fit bolts, (jlrsl, , Code of practice for training and, testing of oxy-acetylene welders, Low and medium alloy steel covered, electrodes, for manual metal arc, welding (third revision), , 3757:1985, 4000:1992, 4326:1993, , 118, , revision), , Specification, for high strength, structural bolts (second revision), Code of practice for high strength, bolts in steel structures tjirst revision), Code of practice for earthquake, resistance design and construction of, buildings (second revision)

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-, , IS 800:2007, , Title, , IS No., , Title, , revision), , (Part 1): 1974, 7318 (Part 1):, 1974, , Specification for plain washers with, outside diameter =3x inside dkmeter, Taper washers for channels (ISMC), , 7557:1982, , Part 1 Fusion welding of steel, Approval test for welders when welding procedure, approval, is not, required: Part 1 Fusion welding of, steel, Specification, for steel wire (upto, 20 mm) for the manufacture of cold, forged rivets @rst revision), Geometrical tolerancing on technical, drawings:, Tolerances of form, orientation, location and run-out, and appropriate, (Jirsf, geometrical, definitions, , IS No., 5369:1975, , 5370:1969, 5372:1975, , General, washers, , requirements, for plain, and lock washers (first, , tjlrst revision), , 5374:1975, , Taper washers for I-beams (ISMB), , 5624:1993, , Foundation bolts — Specification, (first revision), Hot rolled steel plate (upto6 mm), sheet and strip for the manufacture of, low pressure liquefiable gas cylinders, — Specification (third revision), Welding rods and bare electrodes for, gas shielded arc welding of structural, steel (first revision), Molybdenum, and chromiummolybdenum low alloy steel weldlng, rods and bare electrodes, for gas, shielded arc welding (jirst revision), Specification for heavy washers for, steel structures, High strength structural, nuts —, Specification (first revision), Specification for hexagonal bolts for, steel structures, Specification, for hardened, and, tempered washers for high strength, structural bolts and nuts @rst revision), Safety code for erection of structural, steelwork, Specification, for tolerances, for, fabrication of steel structures, Specification for bare wire electrodes, for submerged, arc welding, of, structural steels, Approwd tests for welding procedures:, Part 1 Fusion welding of steel, Approval tests for welders working, to approved welding procedures, , (jlrst revision), , 6240:1999, , 6419:1996, , 6560 ; 1996, , 6610:1972, 6623:2004, 6639:1972, 6649:1985, , 7205:1974, 7215:1974, 7280:1974, , 7307, (Part 1): 1974, 7310, , 8000, (Part 1) : 1985/, 1S0 1101:1983, , revision), (Part 2): 1992/, 1S0 2692:1988, (Part 3): 1992/, 1S0 1660:1987, (Part 4): 1976, 8976:1978, , 9077:1979, , 9172:, , 979, , 9295:, , 983, , 9595:1996, , 10748:2004, , Maximum material principles (first, , revision), Dimensioning, and tolerancing, of, profiles (second revision), Practical examples of indications on, drawings, Guide, for, preparation, and, arrangement of sets of drawings and, parts lists, Code of practice, for corrosion, protection of steel reinforcement in, RB and RCC construction, Recommended, design practice for, corrosion, prevention, of steel, structures, Steel tubes for idlers for belt, conveyors @rst revision), Metal arc welding of carbon and, carbon, manganese, steels, —, (first revision), Recommendations, Hot-rolled, steel strip for welded, tubes and pipes — Specification, , (second revision), 12843:1989, SP6 (1): 1964, , 119, , Tolerances, for erection of steel, structures, Handbook for Structural Engineers —, Structural Steel Sections

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IS 800:2007, ANNEX, [Clause, ANALYSIS, , B-1 ADVANCED STRUCTURAL, DESIGN, , B, , 4.1. 1(c)], , AND DESIGN, , METHODS, , B-2.2 Design Bending Moment, , ANALYSIS AND, , The design bending moment under factored load shall, be taken as the maximum bending moment in the length, of the member. It shall be determined either:, , B-1.l Analysis, For a frame, comprising members of compact section, with full lateral restraint, an advanced structural, analysis may be carried out, provided the analysis can, be shown to accurately model the actual behaviour of, that class of frames. The analysis shall take into, account the relevant material properties, residual, stresses, geometrical imperfections,, reduction in, stiffness due to axial compression,, second-order, effects, s.ecti~n strength, and ductility,, erection, procedures and interaction with the foundations., , a), , directly from the second-order, , b), , approximately, if the member is divided into, a sufficient number of elements, as the greatest, of the element end bending moments; or, , c), , by amplifying the calculated design bending, moment, taken as the maximum bending, moment along the length of a member as, obtained by superposition of the simple beam, bending moments determined by the analysis., , analysis; or, , Advanced structural analysis for earthquake loads shall, take into account, as appropriate the response history,, torsional, response,, pounding, against, adjacent, structures, and strain rate effects., , For a member with zero axial force or a member subject, to axial tension, the factored design bending moment, shall be calculated as the moment obtained from second, order analysis without any amplification., , B-1.2 Design, , For a member with a design axial compressive force, as determined from the analysis, the factored design, bending moment shall be calculated as follows:, , For the strength limit state, it shall be sufficient to, satisfy the section capacity requirements of Section 8, for the members subjected to bending, of Section 7 for, axial members, of Section 9 for combined forces and, of Section 10 for connections., Effect of moment, magnification given in Section 9, instability given in, Section 7 and lateral buckling given in Section 8 need, not be considered while designing the member, since, advanced analysis methods directly consider these., , M = &Mm, where, 5,, , = moment amplification factor for a braced, member determined, in accordance with, Section 9., , B-3 FRAME, An advanced structural analysis for earthquake loads, shall recognize that the design basis earthquake loads, calculated in accordance with IS 1893 is assumed to, correspond to the load at which the first significant, plastic hinge forms in the structure., B-2 SECOND, DESIGN, , INSTABILITY, , ANALYSIS, , B-3.1 Analysis, Frame instability, as treated here, is related to the design, of multi-storey rigid-jointed frames subject to side, sway. The elastic critical load factor, k~~ may be, determined, using the deflection, method as given, in B-3.2 or any other recognized method. This is used, to calculate the amplified sway moments for elastic, designs and to check frame stability in plastic designs., The elastic critical load factor, LC, of a frame is the, ratio by which each of the factored loads would have, to be increased to cause elastic instability., , ORDER ELASTIC ANALYSIS AND, , B-2.1 Analysis, In a second-order elastic analysis, the members shall, be assumed to remain elastic, and changes in frame, geometry under the design load and changes in the, effective stiffness of the members due to axial forces, shall be accounted for. In a frame where the elastic, buckling load factor (AC,)of the frame as determined, in accordance with 4.6 is greater than 5, the changes, in the effective stiffness of the members due to axial, forces may be neglected., , B-3.2 Deflection, , Method, , An accurate method of analysis (ordinary linear elastic, analysis) should be used to determine the horizontal, deflections of the frame due to horizontal forces applied, at each floor level, which is equal to the notional, horizontal load in 4.3.6. Allowance should be made, 120

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IS 800:2007, that storey of area A, given by:, , for the degree of rigidity of the base as given in B-3.2, in this deflection calculation., The base stiffness should be determined, to 4.3.4., , by reference, , The elastic critical load factor, AC,is calculated, , as:, , where, h = storey height;, , AC,=, , 1, 200@s,M,x, , b = width of the braced bay;, , z, , where, , KC = sum of the stiffness I,L, of the columns, in that storey;, , 4s, Max= largest value of the sway inde~y OSgiven, , h’ ~SP, , kj =, , where, h=, , ~SP, , = surnof spring stiffness horizontal, , force, , per unit horizontal deflection of all the, panels in that storey determined from:, , storey height,, , 8“ = horizontal deflection of the top of the storey, due to the combined gravity and notional, loads, and, %=, , s 2; and, , 80E~ Kc, , Sp=, , horizontal deflection of the bottom of the, storey due to gmvity and notional load., , 0.6h lb, [l+(@l’’pEp, , where, , B-3.3 Partial Sway Bracing, , ‘P = thickness of the wall panel, and, , In any storey the stiffening effect of infill wall panels, may be allowed for by introducing a diagonal strut in, , EP = modulus of elasticit y of the panel material., , C, , ANNEX, [Clauses, , 5.2.2.2(b), , and 5.6.2], , DESIGN AGAINST FLOOR VIBRATION, corresponds approximately to 0.5 percent g, where g, is the acceleration, due to gravity. Continuous, vibration is generally more annoying then decaying, vibration due to damping. Floor systems with the, natural frequency less than 8 Hz in the case of floors, supporting rhythmic activity and 5 Hz in the case of, floors supporting normal human activity should be, avoided., , C-1 GENERAL, Floor with longer spans of lighter construction and less, inherent damping are vulnerable to vibrations under, normal human activity. Natural frequency of the floor, system corresponding to the lowest mode of vibration,, damping characteristics, are important characteristics, in floor vibration. Open web steel joists (trusses) or, steel beams on the concrete deck may experience, walking vibration problem. Fatigue, overloading of, floor systems and vibrations due to rhythmic activities, such as aerobic or dance classes are not within the scope, of this Annex., C-2 ANNOYANCE, , C-3 FLOOR, , FREQUENCY, , The fundamental natural frequency can be estimated, by assuming full composite, action, even in noncomposite construction. This frequency,$, for a simply, supported one way system is given by, , CRITERIA, , In the frt?quency range of 2 to 8 Hz in which people, are most sensitive to vibration, the threshold level, , j = 156~*, , 121

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,.,,,,,, , 1 111, , II, , ., , “-, , IS 800:2007, where, modulus of elasticity, , E=, IT, , =, , of steel, MPa;, , transformed moment of inertia of the one, way system (in terms of equivalent steel), assuming the concrete flange of width equal, to the spacing of the beam to be effective,, in mm4;, , f,=, , span length, in mm; and, , w=, , dead load of the one way joist, in N/mm., , Critical Damping, Percent, , (1), , (2), , (3), , 2, 3-4, 6, up to 12, , C-5 ACCELERATION, The peak acceleration aO, from heel impact for floors, of spans greater than 7m and natural frequency f], less, than 10 Hz may be calculated as:, , 11, —=7++, A, , System, , i) Fully composite construction, ii) Bare steel beam and concrete deck, iii) Ftoor with finishes, false ceiling,, fire proofing, ducts furniture, iv) Partitions not located atong a, support or not spaced father apart, than 6 m and partitions oriented in, orthogonal dwtions, , If the one way joist system is supported by a flexible, beam running, perpendicular, with the natural, frequency fz, the floor frequency may be reduced to, ~, given by:, , fr2, , S1, No., , aOlg = 600 f, /W, , f,, , where, C-4 DAMPING, The percentage of critical damping, approximately as given below:, , ANNEX, (Clause, DETERMINATION, , total weight of floors plus contents over the span, length and equivalent floor width (b), in N;, , b=, , 40t, (20 t,when over hang is only on one, side of the beam);, , t,, , = equivalent thickness of the slab, averaging, concrete in slab and ribs; and, , t?, , = acceleration, , due to gravity., , D, 7.2.2), , OF EFFECTIVE, , LENGTH, b), , D-1 METHOD FOR DETERMINING EFFECTIVE, LENGTH OF COLUMNS IN FRAMES, In the absence of a more exact analysis, the effective length, of columns in framed structures may be obtained by, multiplying the actual length of the column between the, centres of laterally suppotting members (beams) given, in Fig. 27 and Fig. 28 with the effective length factor K,, calculated by using the equations given below, provided, the connection between beam and column is rigid type:, a), , w=, may be assumed, , OF COLUMNS, , Sway Frames (Moment Resisting Frames), [see 4.1.2(b)], The effective length factor K, of column in, sway frames is given by (see Fig. 28):, , K_, , l-o.2(p,, , -[, , +p2)-o.12p,/?2, , 1– 0.8(~1 .+ /32)+ 0.6Fipz, , 1, 0’5, , where, , Non-sway Fmmes (BracedFrame) [(see 4.12(a)], A frame is designated as non-sway frame if, the relative displacement, between the two, adjacent floors is restrained by bracings or, shear walls (see 4.1.2). The effective length, factor, K, of column in non-sway frames is, given by (see Fig. 27):, [1+0.145, , Kc, Kb =, , (#, [email protected]/32], , effective flexural stiffness of the, columns and beams meeting at the, joint at the ends of the columns, and rigidly connected at the joints,, and these are calculated by:, , K= C(I/L), , K= [2- O.364(fl, + ~, )- 0.247~,/3, ], , 122

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.,, , “—---, , . _, , IS 800:2007, , HINGED 1, 0.90.80.70.60.5t, a-, , o,40.3 0.2 “, 0.1 “, , FIXED, , 0.0, , 0, ‘*, o, , I, 0.1, , I, 0.2, , I, 0.3, , I, 0.4, , I, 0.5, , I, 0.6, , 1, , I, , I, , 0.7, , 0.8, , 0.9, , FIXED, , 1, HINGED, , P,—————, FIG. 27 COLUMN EFFECTIVE LENGTH FACTOR — NON-SWAY FRAME, PINNED, , ai, , FIXED, FIXED, , PINNEC), P,~, , FIG. 28 COLUMNEFFECTIVELENGTHFACTOR— SWAY FRAME, , 123

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IS 800:2007, I = moment of inertia of the member about, an axis perpendicular to the plan of the, frame., , Coefficient K, for effective length of bottom part of, double stepped column shall be taken from the formula:, , L = length of the member equal to centreto-centre distance of the intersecting, member., C = correction, , ‘,=m, , factor as shown in Table 35., , where, , Table 35 Correction Factors for Effective, Flexural Stiffness, S1 Far End Condition, , Correction, , No., , (1), , Factor, C, , A, , r’, , i) Pinned, , 1.5(1-ti), , tl, , =, , lower and middle parts, , 1.0(1 - 0.2Z), , 2.0(1 -0.4E), , and Kl are taken from Table41., , I’,v = average value of moment of inertia for the, , 1.5(1-E), , ii) Rigidly connected to column 1.0(1– ii), iii) Fixed, , Kz,, , ., , BracedFrame UnbraeedFrame, (3), (4), , (2), , K,,, , =, , IILl i- IZLZ, LI + L,, , 0.67(1 - 0.4E), , 1“,, = average value of moment of inertia for the, middle and top parts, , ‘c, , where, P. = elastic buckling load, and, P = applied load., , =, , IZLZi- I~L~, L, + L,, , Value of coefficient, given by formula:, , D-2 METHOD FOR DETERMINING EFFECTIVE, LENGTH FOR STEPPED COLUMNS (see 7.2.2), , Kz for middle part of column is, , K2=~,, D-2.1 Single Stepped Columns, coefficient, by:, , Effective length in the plane of stepping (bending about, axis Z-Z) for bottom and top parts for single stepped, column shall be taken as given in Table 36., , FOR, , KS for the top part of the column is given, , K3+3, , NTOTE— The provisions of D-2.1 are applicable to intermediate, columns as well with stepping on either side, provided, appropriate ValWs Of 1,and [j are taken., , D-3 EFFECTIVE, LENGTH, STEPPED COLUMNS, , and, 2, , 3, , where, c2=~, , DOUBLE, , Effective lengths in the plane of steppings (bending, about axis Z-Z) for bottom, middle and top parts for a, double stepped column shall be taken as follows, (see also Fig. 29):, , II (P2+P3), L, [ 12(~+P2+P, ), c3=:m, , NOTE — The provisions of D-3 are applicable to intermediate, columns as well with steppings on either side, provided, appropriate, values, of I,, 12and It are taken., , P3, , P3, , p2 /3, , L!3, , i-----, , p, /2, , L2, +, L,, , /1, , J, , ‘1, , (a), , p213, , L\, , I“av, , r, , r, , ,3, , L3, , L2+L3, P,, , L, , L,, i--, , t, , t, , L1+L2, , L,+L2, /’ av, , “, , 1, , 1-, , 11, (c), , (b), , ‘+F, YI, , FIG. 29 EFFECTIVE LENGTH OF DOUBLE STEPPED COLUMNS, 124, , f’,“, 1-, , (d)

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IS 800:2007, Table 36 Effective Length of Single Stepped Columns, (Clause D-2. 1), SI, , Degree of End Restraint, , Sketch, , Effeetive Length Coefficients, , (2), , (3), , (4), , No., , (1), i), , Column Parameters, All Cases, (5), , held in position, against, and restrained, rotation at both ends, , Effectively, , tl, , -1, , 71, , 1, , 12, , where, , Effectively held in position, at both ends and restrained, against rotation at bottom, end only, , 1,, , K,zand K,!areto, per Table 37, , 33, ii), , for, , be taken as, , 1, , ‘=J’w7-, , Ii?, , L1, , Kz=&3, I, , where, , K,zand Kll are to be taken as, per Table38, , iii), , Effectively held in position, and restrained against, rotation at bottom end, and, top end held against, rotation but not held in, position, , K, to be taken as per Table39, Effective length, , pal, , of, , of, , bottom, , in plane 01, , column, , stepping = KVLI, 1, , iv), , Effectively held in position, and restrained against, rotation at bottom end, and, top end neither held against, rotation nor held in, position, , K, to be taken as per Table40 Effective length of top part o], column in plane of stepping=, K~L2, , 1,, , !1,, I, , Table 37 Coeftlcients, , of Effective Lengths K12and K,, for columns with Both Ends Effectively Heid in, Position and Restrained Against Rotation, , (Table 36), , i’, Coeftlcients, 12/1[, , 0.1, , 0.2, , 0.3, , 0.4, , 0.5, , 0.6, , 0.7, , K12and KII for LJLI Equal to, 0.8, , 0.9, , 1.0, , 1.2, , L4, , 1.6, , 1.8, , 2.0, , 2.67, 2.20, 1.72, 1.48, 1.23, 1.23, 1.00, , 3.03, 2.40, 1.92, 1.67, 1.39, 1.39, 1.10, , 3.44, 2.60, 2.11, 1.82, 1.53, 1.53, , 3.85, 2.86, 2.28, 1.96, 1.66, 1.66, , 4.34, 3.18, 2.45, 2.12, 1.79, 1.79, , 4.77, 3.41, 2.64, 2.20, 1.92, 1.92, , 1.20, , 1.30, , 1.40, , 1.50, , Coefficient KU (PI =0), , 0.05, , 0.1, 0.2, 0.3, 0.4, 0.5, 1.0, , 0.74, 0.67, 0.64, 0.62, 0.60, 0.59, 0.55, , 0.94, 0.76, 0.70, 0.68, 0.66, 0.65, 0.60, , 1.38, 1.00, 0.79, 0.74, 0.71, 0.70, 0.65, , 1.60, 1.20, 0.93, 0.85, 0.77, 0.77, 0.70, , 1.87, 1.42, 1.07, 0.95, 0.82, 0.82, 0.75, , 2.07, 1.61, 1.23, 1.06, 0.93, 0.93, 0.80, , 2.23, 1.78, 1.41, 1.18, 0.99, 0.99, 0.85, , 2.39, 1.92, 1.50, 1.28, 1.08, 1.08, 0.90, , 2.52, 2.04, 1.60, 1.39, 1.17, 1.17, 0.95, , PZ, L,, , i, ~, /1, , ‘1, 3, , Coefficient K,, (Pz = O), II, , 0.05, , 0.65, 0.64, 0.62, 0.60, 0.58, 0.57, 0.55, , 0.67 0.71 0.85 1.01 1.17 1.31 1.41, 0.1, 0.65 0.65 0.65 0.78 0.92 1.05 1.15, 0.2, 0.64 0.65 0.65 0.66 0.73 0.83 0.92, 0.3, 0.63 0.64 0.65 0.66 0.67 0.73 0.81, 0.4, 0.63 0.63 0.64 0.64 0.66 0.68 0.75, 0.5, 0.61 0.63 0.64 0.64 0.65 0.68 0.72, 1.0, 0.58 0.60 0.61 0.62 0.63 0.65 0.67, NOTE — Intermediate value maybe obtained by interpolation., , 1.50, 1.25, 1.01, 0.89, 0.82, 0.77, 0.70, , 125, , 1.57, 1.33, 1,09, 0.94, 0.88, 0.83, 0.73, , 1.67, 1.45, 1.23, 1.09, 1.01, 0.94, 0.80, , 1.74, 1.55, 1.33, 1.20, 1.10, 1.04, 0.88, , 1.78, 1.62, 1.41, 1.28, 1.19, 1.12, 0.93, , 1.82, 1.68, 1.48, 1.35, 1.26, 1.19, 1.01, , 1.86, 1.71, 1.54, 1.41, 1.32, 1.25, 1.05, , 1, 1, P, +P2, , L,, -1

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H 800:2007, Table 38 Coet%cients of Effective Lengths Klz and Kll for Columns with Both Ends Effectively, Position and Restrained Against Rotation at Bottom End Only, , Held in, , (Table 36), Coef!lcients, 1,/1,, , 0.2, , 0.1, , 0.3, , 0.4, , 0.5, , 0.6, , 0.7, , K,z and IfII for L@, Equal to, 0,8, 0.9, 1.0, 1,2, 1.4, , Coefficient KU(P1= O), , 0.05, , 0.97, 0.83, , 1.66, 1.21, , 0.3, , 0.78, , 0.90, , 1.09, , 0.5, I.0, , 0.78, 0.78, , 0.86, 0.85, , 0.99, 0.92, , o.I, , 0.05, 0.1, 0.3, 0.5, 1.0, , 0.67, 0.67, 0.67, 0.67, 0.67, , 2.10, 1.57, , 0.67 ;0,82, 0.67 0.73, 0.67 0.67, 0.67 0.67, 0.67 0.67, , 2.43, 1.95, 1.27, 1.10, 0.99, 1.16, 0.93, 0.71, 0.69, 0.68, , 2.72, 2.14, 1.44, 1.22, 1.06, 1.35, 1.11, 0.80, 0.73, 0.71, , 2.92, 2.33, 1.60, 1.35, 1.13, , 3.08, 2,46, 1.74, 1.47, 1.20, , 3.24, 2.60, 1.86, 1.57, 1.27, , 3.48, 2.76, 1.98, 1.67, 1.34, , CoetYfcientK,, (P, = O), 1.48 1.58 1,65 1.69, 1.25 1.36 1.45 1.52, 0.90 0.99 1.08 1.15, 0.81 0.87 0.94, 1.01, 0.74 0.78 0.82 0.87, , 8’, 4., 3 8, Z 5, 1I, 1:$4, ,,, , 3.73, 2.91, 2,11, 1.76, 1.41, 1.74, 1.57, 1.22, 1.07, 0.91, , 1.6, , 1.8, 2,0, .,, P2, L2, ,,, ,,, , ,,, ;,, ,t, 5.36@:4Ml @981’, :. ~~, 4,t33 4.4Yiwi@5Jd , ~~~!’,:, tit, 2.76 2.99 3.2S ‘a, 2.34 2.S0 2.76, 1.82 “,, l.~, 2.10 p, 1,, L,, .,, 1.86 1.88 1,90, A, 1.77 1.80 1,82, 1.48 1;54, 1,.59, ,,, !, :’;;, {“:!, ~“::, Pf +P~, ., ., ., , 4.85, 3.61, 2.51, 2.15, 1.68, , 1.81, 1.66, 1.33, 1.17, , 1.84, 1.72, 1.41, , 0.99, , ;“:, ., , NOTE — Intermediate value maybe obtained by interpolation., , Table 39 Coefficients of Effective Lengths KI for Columns Effectively Held in Position and Restrained, Against Rotation at Bottom End and Top End Held Against Rotation but not Held in Position, , (Table 36), Coefficients K, for 1,/1, Equal to, , c,, , &1, , 0.2, , 0.3, , 0.4, , 0.6, , 0.5, , 0.7, , 0.8, , 0.9, , 1.0, , 1.2, , 1.4, , 1.6, , 1.8, , P2, , 2.0, , o, , 2.0, , 1,8, , 1.7, , 1.67, , 1.6, , 1.55, , 1.50, , 1.4, , I.43, , 1.4, , 1.37, , 1,3, , 1.1, , I.lo, , 1.0, , 0,5, , 2.0, , 1.9, , 1.8, , 1.74, , 1.6, , 1.65, , 1.61, , 1.5, , 1.55, , 1,5, , —, , —, , —, , —, , —, , I .0, , 2.0, , 2.0, , 2.0, , 2.00, , 2.0, , 2.00, , —, , .—, , —, , —, , ——, , 1.5, , 2.0, , 2,2, , 2.3, , 2.48, , —, , ., , —, , —, , —, , —, , —, , 2.0, , 2.0, , 2.6, , 2.9, , –-, , —, , —, , —, , —, , —, , ——, , —, , 2.5, , 2.5, , 3.1, , 3.5, , —, , —, , —, , —, , —, , —, , —, , ——, , —, , 3.0, , 3.0, , 3.7, , 4.1, , —, , —, , —, , —, , —, , —, , —, , —, , L2, , t, PI, , ‘2, , NOTE —, , Intermediate, , values, , may, , be obtained, , —, , —, , —, ., , —, , /1, 1, , F, , !, p, +p2, , —, , —, , L,, , by interpolation,, , Table 40 Coefficients of Effective Lengths K, for Columns with Top Ends Free and Bottom End, Effectively Held in Position and Restrained Against Rotation, (Table 36), Coefficients, , K, for IJIt Equal to, P2, , C,, 0, , 0.1, 2.0, , 0.2, , 0.4, , 2.0, , 0.6, , 2.0, , 0.8, , 2.0, , 2.0, , 1.0, 2.0, , 1.2, 2.0, , 1.4, 2.0, , 0.5, , 2.0, , 2.14, , 2.24, , 2.36, , 2.47, , 2,57, , 2.67, , 2.76, , 1,0, , 2.0, , 2.73, , 3.13, , 3.44, , 3.74, , 4,00, , —, , —, , 1.6, 2.0, 2,85, , 1.8, 2,0, , 2.0, , 2.5, , 2.0, , 2.0, , 2.0, , 2.94, , 3,02, , —, , —, , —, , —, , —, , 1.5, , 3,0, , 3.77, , 4.35, , 4.86, , —, , —, , —, , —, , 2.0, , 4.0, , 4.90, , 5.67, , —, , —, , —, , —, , —, , —, , 2,5, , 5.0, , 6,08, , 7.00, , —, , —, , —, , —, , —, , NOTE —, , Intermediate, , —, , maybe, , obtained, , —., —., , ——, values, , 10, 2.0, , 20, , I, , 2.0, , —, —, , by interpolation., , 126, , —, , —, , —, , —, , —, , —, , —, , —, —, , t-2, , r, , 4, P,, , J, ‘2, , /1, , —, , 3.06,07.25————, , 5.0, , L,, , J, , t, , P,+pz

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IS 800:2007, ANNEX, , E, , (Clause 8.2.2.1), ELASTIC, E-1 ELASTIC, , CRITICAL, , LATERAL TORSIONAL, , MOMENT, , BUCKLING, , E-1.2 Elastic, Critical, Moment, Symmetrical About Minor Axis, , of a Section, , E-1.l General, In case of a beam which is symmetrical only about the, minor axis, and bending about major axis, the elastic, critical moment for lateral torsional buckling is given, by the general equation:, , The elastic critical moment is affected by:, a), , Moment gradient in the unsupported, , b), , Boundary, points,, , c), , Non-symmetric and non-prismatic, the member, and, , d), , conditions, , Location of transverse, shear centre., , The boundary conditions, two components:, a), , b), , length,, , at the lateral support, , X2EIY, ——, , nature of, ‘c,, , = C1 (L,,), , load with respect to, , ~[(, ), ~+, , K, Kw, , 2I, 1,, , 0,5, ‘J, GI, (LLT )2, Y + (c2Yg – c3Yj )-], rr2EI, , C2Yg – c3Yj ), -(, , at the lateral supports have, , 1, , Torsional restraint — Where the cross-section, is prevented from rotation about the shear, centre, and, , where, cl,, , Warping restraint — Where the flanges are, prevented from rotating in their own plane, about an axis perpendicular to the flange., , c2~ C3, , =, , factors depending upon the loading and, end restraint conditions (see Table 42)., , K= effective, , length, factors, of the, unsupported, length accounting, for, boundary conditions at the end lateral, supports. The effective length factor K, varies from 0.5 for complete restraint, against rotation about weak axis to 1.0, for free rotate about weak axis, with 0.7, for the case of one end fixed and other, end free. It is analogous to the effective, length factors for compression members, with end rotational restraint., , The elastic critical moment corresponding to Iaterd, torsional buckling of a doubly symmetric prismatic, beam subjected to uniform moment in the unsupported, length and torsionally restraining lateral supports is, given by:, , KW = warping restraint Factor. Unless special, where, , provisions to restrain warping of the, section at the end lateral supports are, made, KWshould be taken as 1.0., , IY,I,., 1, = moment of inertia about the minor axis,, warping constant and St. Venants torsion, constant, of, the, cross-section,, respectively;, , Yg = y distance, , between, the point of, application of the load and the shear, centre of the cross-section and is positive, when the load is acting towards the shear, centre from the point of application., , G = modulus of rigidity; and, LLT = effective length against lateral torsional, buckling (see 8.3)., This equation in simplified form for I-section has been, presented in 8.2.2.1., While the simplified equation is generally on the safe, side, there are many situations where this may be very, conservative. More accurate calculation of the elastic, critical moment for general case of unsymmetrical, sections, loading away from shear centre and beams, with moment gradient can be obtained from specialist, literature,, by using an appropriate, computer, programme or equations given below., , Yj, , =, , y,, , =, , Y, -o.5\A(z2, , -y2)ydA/Iz, , co-ordinate, of the shear centre with, respect to centroid, positive when the, shear centre is on the compression side, of the centroid., co-ordinates of the elemental area with, respect to centroid of the section., can be calculated by using the following, approximation:, , 128

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IS 800:2007, a), , where, , Plain flanges, Yj = 0.8, , (z~f-, , 1), , hy/2.O, , A., , (when ~~ > 0.5), , b, t = breadth and thiCkness of the elements, of the section,, respectively., , Lipped flanges, Yj =0.8 (2&- 1) (1+ h~/h) hY/2, (when fl~> 0.5), Yj = (2&, , -, , 1) (1+, , The warping, given by:, , I w=, , hL/h) hY/2, , (when flf S 0.5), , h, hY, , It, , = height of the lip,, = overall, height, section, and, , of, , = O for angle, Tee, narrow, rectangle, section, and, approximately, for hollow, sections, , the, , = distance, between, shear, centre of the two flanges of, the crmis-section., , &, , = IfC/(IfC+ If,) where lfC,lf(are, the moment of inertia of the, compression, and tension, flanges, respectively, about, the minor axis of the entire, section., , = torsion constant, given by:, = ~biti’, , /3 for open section, , = 4A~2 f~(blt), section, , constant,, , (l–~f) ~f [YhY2for I-sections, mono-symmetric, about, weak axis, , where, hL, , by, , the section, and, , yj = 1.0 (2~f - 1) h~/2.O, (when ~~ < 0.5), b), , = area enclosed, , for hollow, , Table 42 Constants cl, Czand c~, (Clause E-1.2), Loading and Support Conditions, , Bending Moment Diagram, , Constants, , Value of K, ~, , (1), , (3), , (2), , VJ=+l, , 1,0, 0.7, 0.5, , V= +314, , 1.0, , $===+’, , I .000, 1.113, 1.144, , 1.000, 1.000, I .000, , 0.998, 1.565, 2.283, , 0.7, 0.5, , 1.323, 1.473, 1.514, , —, , 0.992, 1.556, 2.271, , t ,0, 0.7, 0.5, , 1.563, I .739, 1.788, , —, , 0.977, 1.531, 2.235, , I ,0, 0,7, 0.5, , 1.879, 2.092, 2.150, , —, , 0.939, 1.473, 2.150, , 1.0, 0.7, 0.5, , 2.281, 2.538, 2.609, , —, , 0.855, 1.340, 1.957, , 1.0, , 2.704, 3.009, 3.093, , —, , 0.676, 1,059, 1.546, , 2.927, 3.009, 3.093, , —, , 0.366, 0.575, 0,837, , 2.752, 3.063, 3.149, , —, , 0.000, 0.000, 0.000, , 1.0, , 1.0, 0.7, 0.5, , 1,0, 0.7, 0.5, , 129, , (6), , —, , 0.7, 0,5, , -, , (5), , 1.141, 1.270, 1.305, , 0.7, 0.5, V=+I12, , (4)

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IS 800:2007, Table 42 (Conclude@, Loading and Support Conditions, , Bending Moment Diagram, , Valne of K, , Constants, c, , (2), , (1), , 7, :), , (%, , (3), , (2), , 1.0, 0.5, , 1.132, , 0.459, , 0.525, , 0.972, , 0.304, , 0.980, , 1.0, 0.5, , 1.285, 0.712, , 1.562, 0.652, , 0.753, 1.070, , 1.0, 0.5, , 1.365, 1.070, , 0.553, 0.432, , 1.780, 3.050, , I.0, 0.5, , 1.565, 0.938, , 1.257, 0.715, , 2.640, 4.800, , 1.0, , 1.046, , 0.430, , 1.120, , 0.5, , 1.010, , 0.410, , 1.390, , *, , IF, i, , 1, , /F, Illlllw, , L/4, , L/4~L/4, , 1/4, , ANNEX, (Clause, , F, 10.6.1), , CONNECTIONS, should the strength developed be less than 50 percent, of the effective strength of the material spliced. Wherever, possible in welded construction, flange plates shall be, joined by complete penetration butt welds. These butt, welds shall develop the full strength of the plates., Whenever the flange width or thickness changes at the, splice location, gradual transition shall be made in the, width/thickness of the larger flange., , F-1 GENJ3RAL, The requirement for the design of splice and beam to, column connection as well as recommendation for their, design shall be as given below., F-2 BEAM SPLICES, F-2.1 For rolled section beam splices located away, from the point of maximum, moment, it may be, assumed that the flange splice carries all the moment, and the web splice carries the shear (see Fig. 30)., However in the case of a deep girder, the total moment, may be divided between the flange and the web in, accordance, with the stress distribution., The web, connection should then be designed to resist its share, of moment and shear. Even web splice is designed to, carry only shear force, the moment about the centroid, of the bolt group on either side of the splice should be, designed for moment due to eccentricity., , F-2.3 When beam splice is located at the point of, inflection of a continuous beam, the flange splicing, requirement given above may be relaxed appropriately., F-3 COLUMN, , SPLICE, , F-3.1 Where the ends of compression members are, faced for bearing over the whole area, they shall be, spliced to hold the connected parts aligned. The ends, of compression, members faced for bearing shall, invariably be machined to ensure perfect contact of, surfaces in bearing (see Fig. 31)., , F-2.2 Flange joints should preferably not be located at, points of maximum stress. Where splice plates are used, (see Fig. 30), their area shall not be less than 5 percent, in excess of the area of the flange element spliced; and, their centre of gravity shall coincide, as nearly as possible, with that of the element spliced. There shall be enough, fasteners on each side of the splice to develop the load, in the element spliced plus 5 percent but in no case, , F-3.2 Where such members are not faced for complete, bearing the splices shall be designed to transmit all the, forces to which the member is subjected at the splice, location., F-3.3 Wherever possible, splices shall be proportioned, and arranged so that centroidal axis of the splice, 130

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IS 800:2007, r, , , ,, , I I, , I, , 1 I I, , I, , 1, , ,, , I, }, , 1’, , I, I, I, , I 1I, I, , I I, , I, , I, , II, , I, I, , ,, , ,, , I, , I I, , I, , I 1, , I, , 1, , -! -, , I, , I, , 00, 00, 00, 00, L00, , v, , i, , I, II, , I, , I, /, , Md, , .1, , I, I, I, I, -, , {, , -1, VM, , \, , ?, , ), , 7, , I, , Y, , I, , “, , 11,11,, , II, , I, , 1 1 \, I, , SPLICE PIATE, (OPTIONAL), , I, , VEW!!RED, UNDERDESIGN, , INNER SPLICE PLATE\, (OPTIONAL), 30A Conventional Splice (Typical), , 306 End Plate Splice, , FIG. 30 BEAM SPLICES, , coincides as nearly as possible with the centroidal axes, of the members joined, in order to avoid eccentricity;, but where eccentricity, is present in the joint, the, resulting stress considering, eccentricity, shall be, provided for., F-3.4 If a column flange is subjected to significant, tension or if the faces are not prepared for bearing, or, if full continuity is required without slip, only HSFG, bolts shall be used., , separate lateral load resisting system is to be provided, in the form of bracings or shear walls. The connections, shown in Fig. 32 (A), (B), (C) and (D) can be assumed, as simple connections in framed analysis and need to, be checked only for the transfer of shear from beam to, column., F-4.2 Rigid Connections, In high-rise, and slender, structures,, stiffness, requirements may warrant the use of rigid connections., Rigid connections transfer significant moments to the, columns and are assumed to undergo negligible, deformations at the joint. These are necessary in sway, frames for stability and also contribute in resisting, lateral loads. The connections shown in Fig. 32 (E),, (F), (G) can be assumed as rigid connection in frame, analysis and need to be checked for both shear and, moment transfer from beam to the column. Fully, welded connections can also be considered as rigid, beam to column connections., F-4.3 Semi-rigid, , Semi-rigid connections fall between the two types, mentioned above. The fact is that simple connections, do have some degree of rotational rigidity as in the, semi-rigid connections. Similarly rigid connections do, experience some degree of joint deformation and this, can be utilised to reduce the joint design moments., , FIG. 31 COLUMN SPLICE (TYPICAL), F-4 BEAM-TO-COLUMN, , Connections, , The moment-rotation, relationship of the connections, have to be determined, based on experiments, conducted for the specific design or based on the, relationship derived from tests, presented in specialist, Iiteroture. The simplest method of analysis will be to, idealize the connection as an equivalent rotational, spring with either a bilinear or non-linear moment-, , CONNECTIONS, , F-4.1 Simple Connections, Simple connections are assumed to transfer only shear, at some nominal eccentricity and typically used in, frames up to about five stories in height, where strength, rather than stiffness govern the design. In such frames, 31

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IS 800:2007, , -Fl1, , L, , I, , I, , I, , (s, , I, da, , 0, 0, 0, , 1, r, , I, _t, , ~, , t, D, , I, , 32A Single Web Angle, , I, , 32B Double Web Angle, , 7(i, 1, , f., , L, , II, , 32C Top and Seat Angle with, Double Web Angle, , 32D Top and Seat Angle without, Double Web Angie, , ., , I, , :::--1, --1, , ‘g, , L-tp, , 9, :: ; :2, , --l, , 32E End Plate without Column Stiffeners, , d, , I--tp, , 32F End Plate with Column Stiffeners, , m, t-%, , 00, 00, , dp, , 00, , --l l-+, , II, , 32G T-Stub, , 32H Header Plate, , FIG. 32 SIZE PARAMETER FOR VARIOUS TYPES OF CONNECTION, 132, , I

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—, , IS 800:2007, F-4.3.2 Connection Models, , rotation characteristics., The classification, proposed, by Bjorhovde combined with the Frey-Morris model, can be used with convenience to model semi-rigid, connections, as given in the next section., F-4.3.1 Connection, , Frye-Morris has derived the following polynomial, model for the moment curvature relationship of semirigid connections:, , Classification, , e,=Ckums+ C2UGW3, +C3OWP, where, , Connections are classified according to their ultimate, strength or in terms of their initial elastic stiffness, and Bjorhovde’s classification., It is based on the, non-dimensional, moment parameter (m’ = MU/ MP~), and the non-dimensional, rotation, (01 = 0, /eP), parameter,, where f)P is the plastic rotation., The, Bjorhovde’s classification, is based on a reference, length of the beam equal to 5 times the depth of the, beam. The limits used for connection classification, are shown in Table 43 and are graphically, represented in Fig. 33., , Al = moment at the joint, in kN m;, , K = standardization, , parameter which depend, on the connection type and geometry;, and, , Cl, C2, CS = curve fitting constants, Table 44 shows the curve fitting constants, and standardization constants for FryeMorris Model [All size parameters in the, table are in mm (see Fig. 32)]., , ●, , Table 43 Connection, , Classification, , Limits, , S1 No., , Nature of the Connection, , In Terms of Strength, , (1), , (2), , (3), , i), , ii), iii), , Rigid connection, Semi-rigid connection, Flexible connection, , I, , In Terms of, Stiffness, (4), , ml >0.7, , m1~2.50[, , 0.7> m’ >0.2, , 2.5t9’>trr’> 0.58’, , r?r~<0.2, , m’ <0.50’, , \\, , ROTATION, , 1.0, , 0.8, , 0,6, , 0.4, , 0.2, , 0, , 8/= 618P, FIG. 33 CLASSIFICATIONOF CONNECTIONSACCORDING TO BJORHOVDE, 133, , 2.7

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IS 800:2007, Table 44 Connection, , sl, , Type, , Connection, , Constants in Frye-Morris, (Clause F-4.3.2), , Type, , Model, , Curve-Fitting, Constants, , No., , (1), , (2), , i), , A, , Single web angle connection, , ii), , B, , Double web, , iii), , c, , Top and seat angle connectionwith doubleweb, angle, , iv), , D, , Top and seat angle connection without double, web angle, , v), , E, , End plate connectionwithoutcolumnstiffeners, , vi), , F, , End plate connectionwith columnstiffeners, , vii), , G, , T-stubconnection, , viii), , H, , Headerplate connection, , (3), , Standardization, , (4), , where (see Fig. 32), d = depth of beam, , (5), , ~ = ~a-2.4tC.\.81g0.1S, , C,=l.91 x 104, Cz= 1.30X 10”, CJ=2.70 x 10’7, C,=l.64 x 103, CZ=l.t)3 x 10’4, C3=8.18 x 1025, C, =2.24 x 10-’, CZ=I.86 x 104, CJ=3.23 x IOg, CI=I.63 x 103, CZ=7.25 x 10’4, C3=3.31 x 1023, CI=l.78 x 104, CZ=-9.55 x 10’s, C3=5.54 x 1029, CI ‘2.60 x 102, Cj=~.37 x 10”, C3=1.31 x IO*2, c1 =4.05 x 102, C2=4.45 x 10’3, Cj=–2.03 x 1023, CI=3.87, C,=2.71 x 105, C3=6.06X lo”, , angleconnection, , Constants, , ~ = &4 ~C-l,81g0.1S, ~ = ~-!.287ta-l,128tC-0.415, /;13694@, - (3,5@35, ~ = ~- 1.518, -0.5, ~,-0.7~<, 1.1, ~ = ~g-2,4tp.04tf, -1.5, ~ = ~g-2.4,P.0.6, K=d-’”s tC-O’*[,, -07d<’1, , K = t;’’bg’6 d~23tw-os, , /.= thickness of the web angle, in mm, in mm, of flange T-stub, connector,, t.= thickness of web of the beam in the connection, in mm, tP= thickness of end plate, header plate, in mm, l.= length of the angle, in mm, 1,= length of the T-stub connector,in mm, , If= thickness, , d,= depth of the angle, in mm, db= diameter of the bolt, in mm, dg= center-to-centre of the outermost bolt of the end plate, connection, in mm, g = gauge distance of bolt line, I,= thickness of the top angle, in mm, , NOTE — For preliminary analysis using a bilinear moment curvature relationship, the stifthess given in Table 45 may be assumed, , dependingon the type of connection.The valuesare based on the secantstiffnessat a rotationof 0.01 radian and typicaldimensionof, connectingangleand othercomponentsas givenin the table., , Table 45 Secant Stiffness, , (Table 44), s], , Type of Connection, , No., , (2), , (1), , i), ii), iii), iv), , Single web connection angle, Double web-angle connection, Top and seat angle connection without double web, angle connection, Header plate, , Dimension, , Secant Stiffeners, , mm, , kNm/radian, , (3), , (4), , d,=250, f,= 10, g=35, , d,= 250, r,= 10, g= 77,5, da=300, t.= 10, /==]40, db=213, dp= 175, fp= 10, g=75,, , F-5 COLUMN BASES, , tw=7.5, , 1150, 4450, 2730, , 2300, , of the joint between the base plate and the foundation, shall be determined taking account of the material, properties and dimensions of both the grout and the, concrete foundation., , F-5.1 Base Plates, Columns shall be provided with base plates capable of, distributing the compressive forces in the compressed, parts of the column over a bearing area such that the, bearing pressure on the foundation does not exceed, the design strength of the point. The design strength, , F-5.2 Holding Down Bolts (Anchor Bolts), F-5.2.1 Holding down bolts shall be provided if, necessary to resist the effects of the design loads., 134

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IS 800:2007, They shall be designed to resist tension due to uplift, forces and tension due to bending, moments, as, appropriate., , F-5.2.4 If no special elements for resisting the shear, force are provided,, such as block or bar shear, connectors, it shall be demonstrated, that sufficient, resistance to transfer the shear force between the, column and the foundation is provided by one of the, following:, , F-5.2.2 When calculating the tension forces due to, bending moments, the lever arm shall not be taken as, more than the distance between the centroid of the, bearing area on the compression side and the centroid, of the bolt group on the tension side, taking the, tolerances on the positions of the holding down bolts, into account., F-5.2.3 Holding down bolts shall either be anchored, into the foundation by a hook or by a washer plate or, by some other appropriate load distributing member, embedded in the concrete., , a), , Frictional resistance of the joint between the, base plate and the foundation., , b), , Shear resistance, , of the holding down bolts., , c), , Shear resistance, the foundation., , of the surrounding, , d), , Shear and bearing resistance of the shear key, plates welded to the base plate and embedded, in the pedestal/foundation., , part of, , ANNEX G, (Clause 17. 16), GENERAL, , RECOMMENDATIONS, , FOR STEELWORK, , TENDERS, , AND CONTRACTS, , the proposed location and main dimensions, of the building or structure;, , G-1 GENERAL, G-1.l The recommendations given in this Annex are, in line with those generally adopted for steelwork, construction and are meant for general information., , b), , Ground levels, existing and proposed;, , c), , Particulars of buildings or other constructions, which may have to remain on the actual site, of the new building or structure during the, erection of the steelwork;, , d), , Particulars of adjacent buildings affecting, or, affected by, the new work;, , G-1.3 The recommendations, are unsuitable, for, inclusion as a block requirement in a contract, but in, drawing up a contract the points mentioned should be, given consideration., , e), , Stipulation regarding, or time schedule;, , f), , Conditions affecting the position or continuity, of members;, , G-2 EXCHANGE, , g), , Limits of length and weight of steel members, in transit and erection;, , h), , Drawings of the substructure,, existing, showing:, , G-1.2 These recommendations do not form part of the, requirements of the standard and compliance with these, is not necessary for the purpose of complying with this, standard., , OF INFORMATION, , Before the steelwork, design is commenced,, the, building designer should be satisfied that the planning, of the building, its dimensions and other principal, factors meet the requirements of the building owner, and comply with regulations, of all authorities, concerned. Collaboration, of building designer and, steelwork designer should begin at the outset of the, project by joint consideration of the planning and of, such questions as the stanchion spacing, materials to, be used for the construction, and depth of basement., G-3 INFORMATION, REQUIRED, STEELWORK, DESIGNER, , sequence, , proposed, , or, , 1), , levels of stanchion foundations, if already, determined;, , 2), , any details affecting the stanchion bases, or anchor bolts;, , 3), , permissible, foundation;, , 4), , provisions for grouting., In the case of new work, the substructure, , bearing, and, , pressure, , on the, , NOTE —, , BY THE, , should be designed in accordance with the relevant, standards dealing with foundations and substructure., , G-3.1 General, a), , the erection, , j), , Site plans showing in plan and elevation of, 135, , The maximum wind velocity appropriate, the site (see IS 875); and, , to

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IS 800:2007, k), , G-3.2, a), , d), , Accessibility, supply;, , e), , Whether the steelwork contractor will be, required to survey the site and set out or check, the building or structure lines, foundations and, levels;, , f-), , Setting-out plan of foundations,, and levels of bases;, , g), , Cross-sections, and elevations of the steel, structure, as necessary, with large-scale details, of special features;, , h), , Whether the connections are to be bolted,, riveted or welded. Particular attention should, be drawn to connections of a special nature,, such as turned bolts, high strength friction grip, bolts, long rivets and overhead welds;, , j), , Quality, of, identification;, , k), , Requirements, in respect, of protective, paintings at works and on site, galvanizing or, cement wash;, , m), , Approximate dates for commencement, completion of erection;, , Large-scale details should be given of any, special features affecting the steelwork., , n), , The inclusive weight per mz of walls, floors,, roofs,, suspended, ceilings,, stairs and, partitions, or particulars of their construction, and finish for the computation of dead load., , Details of any tests which have to be made, during the course of erection, or upon, completion; and, , P), , Schedule of quantities. Where the tenderer is, required to take off quantities, a list should, be given of the principal items to be included, in the schedule., , Environmental factors, such as proximity to, sea coast,, and corrosive, atmosphere., Reference, to bye-laws, and regulations, affecting, the steelwork, design, and, construction., Further, , Information, , Relating, , to Buildings, , Plans of the floors and roof with principal, dimensions,, elevations and cross-sections, showing heights between floor levels., , b), , The occupancy of the floors and the positions, of any special loads should be given., , c), , The building drawings, which should be fully, dimensioned, should preferably be to the scale, of 1 to 100 and should show all stairs, fireescapes, lifts, etc, suspended ceilings, flues, and ducts for heating and ventilating. Doors, and windows, should be shown, as the, openings may be taken into account in the, computations of dead load., Requirements should be given in respect of, any maximum depth of beams or minimum, head room., , d), , The plans should indicate the floors, which, are to be designed to carry partitions. Where, the layout of partitions is not known, or a, given layout is liable to alteration, these facts, should be specially noted so that allowance, may be made for partitions in any position, (see IS 875)., e), , G-4.2 Additional, , The superimposed, loads on the floors, appropriate to the occupancy, as given in, IS 875 or as otherwise required., , f), , Details of special loads from cranes, runways,, tips, lifts, bunkers, tanks, plant and equipment., , g), , The grade of fire resistance appropriate, occupancy as may be required., , G-4 INFORMATION, REQUIRED, (IF NOT ALSO DESIGNER, ), , b), , Climatic conditions at site-seasonat variations, of temperature, humidity, wind velocity and, direction;, , c), , Nature of soil. Results of the investigation, sub-soil at site of building or structure;, , of, , 136, , pro~isions, , for, , and, , Relating to Buildings, , b), , Plan of g,rillages showing sizes, lengths and, levels of grillage beams and particulars of any, stiffeners required;, , c), , Plans of floor beams showing sizes, lengths, and levels eccentricities and end moments., The beam reactions and details of the type of, connection required should be shown on the, plans;, , d), , Plan of roof steelwork. For a flat roof, the plan, should give particulars similar to those of a, floor plan. Where the roof is pitched, details, should be given of trusses, portals, purlins,, bracing, etc;, , e), , The steelwork drawings should preferably be, to a scale of 1 to 100 and should give, identification marks against all members; and, , f), , Particulars of holes required for services,, pipes, machinery fixings, etc. Such holes, should preferably be drilled at works., , G-4.1 General, listed under G-3.1;, , Information, , and, , stanchions, , Schedule of stanchions giving sizes, lengths, and typical details of brackets, joints, etc;, , BY TENDERER, , All information, , steel,, , of power, , a), , to the, , a), , of site and details

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IS 800:2007, G-4.3 Information Relating to Execution of Building, Work, a), , Supply of Materials;, , b), , Weight of Steelwork, , c), , Wastage of Steel;, , d), , Insurance,, to Site;, , e), , Site Facilities for Erection;, , f), , Tools and Plants;, , g), , Mode and Terms of Payment;, , h), , Schedules;, , j), , k), , for Payment;, , Freight and Transport, , G-8.1 Access to Contractor’s, , The contractor should offer facilities for the inspection, of the work at all stages., G-8.2 Inspection, , from Shop, , G-8.3 Inspection, , Sections., , In addition to the number of copies of the approved, drawings or details required under the contract,, dimensioned shop drawings or details should be, submitted in duplicate to the engineer who should, retain one copy and return the other to the steel supplier, or fabricators with his comments, if any., , G-9 MAINTENANCE, G-9.1 General, Where steelwork is to be encased in solid concrete,, brickwork or masonry, the question of maintenance, should not arise, but where steelwork is to be housed, in hollow fire protection, or is to be unprotected,, particularly, where the steelwork is exposed to a, corroding agent, the question of painting or protective, treatment of the steelwork should be given careful, consideration at the construction stage, having regard, to the special circumstances of the case., , G-6 TIME SCHEDULE, As the dates on which subsequent, trades can, commence, depend on the progress of erection of the, steel framing, the time schedule for the latter should, be carefully drawn up and agreed to by the parties, concerned at a joint meeting., , G-9.2 Connections, , ON SITE, , Where connections are exposed to a corroding agent,, they should be periodically inspected, and any corroded, part should be thoroughly cleaned and painted., , The steelwork contractor should be responsible for the, positioning and Ievelling of all steelwork. Any checking, or approval of the setting out by the general contractor, or the engineer should not relieve the steelwork, contractor of his responsibilities in this respect., , G-9.2.1 Where bolted connections, are not solidly, encased and are subject to vibratory, effects of, machinery, or plant, they should be periodically, inspected and all bolts tightened., , G-8 INSPECTION, References, guidance., , may be made, , on Site, , To facilitate inspection, the contractor should during, all working hours, have a foreman, or properly, accredited charge hand available on the site, together, with a complete set of contract drawings and any, further drawings and instructions which may have been, issued from time to time,, , G*5 DETAILING, , G-7 PROCEDURE, , of Fabrication, , Unless otherwise, agreed, the inspection should be, carried out at the place of fabrication. The contractor, should be responsible for the accuracy of the work, and for any error, which may be subsequently, discovered., , Forced Majeure (Sections and provisions for, liquidation, and damages, for delay in, completion); and, Escalation, , Works, , to IS 7215 for general, , 137

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s, , aQ, =, .., !S, o, , ANNEX H, (Informative), PLASTIC, , PROPERTIES, , Table 46 Plastic Properties, Designation, , (1), LSWB 600, ISWB 600, ISMB 600, ISWB 550, , ., u, 00, , ISLB 600, ISMB 550, ISWB 500, ISLB 550, ISMB 500, ISHB 450, ISHB 450, ISLB 500, ISWB 450, ISHB 400, ISHB 400, ISMB 450, ISLB 450, ISWB 400, ISHB 350, ISHB 350, ISMB 400, ISLB 400, ISWB 350, lSHB 300, ISHB 300, ISMC 400, LSMB350, lSLB 350, lSLC 400, ISWB 300, lSHB 250, ISLB 325, , Weight per, , Seetional, , Metre, , Area, , Depth of Seetion, , Width of, , Thickness, , of, , OF BEAMS, , 4, , of Beams (see also IS 808), Radii ofGyration, , Flange, , Flange, , Thickness of, Web, , (D), , ( b,), , (t,), , (tw), , < (r.), , Section, Modulus, , A, , (r,)’, , Plastic, , (Zez), , (%J, , kg/m, , cmz, , mm, , mm, , mm, , mm, , cm, , cm, , cm’, , cm’, , (2), , (3), , (4), , (5), , (6), , (7), , (8), , (9), , (lo), , (11), , *145.1, *133.7, *122.6, *112.5, *99.5, 103.7, *95.2, *86.3, 86.9, 92.5, 87.2, *75.O, 79.4, 82.2, 77.4, ●72.4, *65.3, 66.7, 72.4, 67.4, *61.5, *56.9, 56.9, 63.0, 58.8, *49.4, 52.4, 49.5, *45.7, 48.1, 54.7, *43.1, , 184.86, 170.38, 156.21, 143.34, 126.07, 132.11, 121.22, 109.97, , 110.74, 117.89, 111.14, 95.50, 10I. I5, 104.66, 98.66, 92.27, 83.14, 85.01, 92.21, 85.91, 78.40, 72.43, 72.50, 80.25, 74.85, 62.93., 66.70, 63.01, 58.25, 61.33, 69.71, 54.90, , 600, 600, 600, 550, 600, 550, 500, 550, 500, 450, 450, 500, 450, 400, 400, 450, 450, 400, 350, 350, 400, 400, 350, 300, 300, 400, 350, 350, 400, 300, 250, 325, , 250, 250, 210, 250, 210, 190, 250, 190, 180, 250, 250, 180, 200, 250, 250, 150, 170, 200, 250, 250, 140, 165, 200, 250, 250, 100, 140, 165, 100, 200, 250, 165, , 23.6, 21.3, 20.8, 17.6, 15.5, 19.3, 14.7, 15.0, 17.2, 13.7, 13.7, 14.1, 15.4, 12.7, 12.7, 17.4, 13.4, 13.0, 11.6, 11.6, 16.0, 12.5, 11.4, 10.6, 10.6, 15.3, 14.2, )1.4, 14.0, 10.0, 9.7, 9.8, , 11.8, , 11.2, 12, 10.5, 10.5, 11.2, 9.9, 9.9, 10.2, 11.3, 9.8, 9.2, 9.2, 10.6, 9.1, 9.4, 8.6, 8.6, 10.1, 8.3, 8.9, 8, 8.0, 9.4, 7.6, 8.6, 8.1, 7.4, 8.0, 7.4, 8.8, 7.0, , 25.01, 24.97, 24.24, 22.86, 23.9a, 22.16, 20.77, 21.99, 20.21, 18.50, 18.78, 20.10, 18.63, 16.61, 16.87, 18.15, 18.20, 16.60, 14.65, 14.93, 16.05, 16.33, 14.63, 12.70, 12.95, 15.48, 14.32, 14.45, I 5.50, 12.66, 10.70, 13.41, , .-, , 5.35, 5.25, 4.12, 5.11, 3.79, 3.73, 4.96, 3.48, 3.52, 5.08, 5.18, 3.34, 4.11, 5.16, 5.26, , 3.01, 3.20, 4.04, 5.22, 5.34, 2.84, 3.15, 4.03, 5.29, 5.41, 2.83, 2.84, 3.17, 2.81, 4.02, 5.37, 3.05, , 3854.2, 3540.0, 3060.4, 2723.9, 2428.9, 2359.8, 2091.6, , 1933.2, 1 8Q8.7, 1793.3, 1742.7, 1543.2, 1558.1, 1444.2, 1404.2, 1350.7, 1223.8, 1171.3, 1131.6, 1094.8, I 020.0, 965.3, 887.0, 863.3, 836.3, 754.1, 779.0, 751.9, 699.5, 654.8, 638.7, 607.7, , Shape Factor, , Modulns, , 4341.63, 3986.66, 3510.63, 3066.29, 2798.56, 2711.98, 2351.35, 2228.16, 2074.67, 2030.95, I 955.03, 1773.67, 1760.59, 1626.36, 1556.33, 1533.36, 1401.35, 1290.19, 1268.69, 1213.53, 1176.18, 1099.45, 995.49, 962.18, 921.68, 891.03, 889.57, 851.11, 825.02, 731.21, 708.43, 687.76, , (z,z/z=), , (12), 1.1265, 1.1262, 1.1471, 1.1257, 1.1522, 1.1492, 1.1242, 1.1526, 1.147 I, 1.1325, 1.1218, 1.1493, 1.1300, 1.1261, 1.1155, 1.1500, 1.1451, 1.1271, 1.1212, 1.1085, 1.1498, 1.1390, 1.1223, 1.1145, 1.1021, 1.1816, 1.1421, 1.1320, 1.1794, 1.1167, 1.1092, 1.1317

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Table 46 (Continued), Designistion, , (1), , %, , ISHB 250, lSMC 350, lSMB 300, [SLC 350, ISLB 300, ISHB 225, ISWB 250, ISHB 225, LSMC300, ISMB 250, ISLC 300, lSLB 275, ISHB 200, lSHB 200, ISWB 225, ISMC 250, ISMB 225, ISLB 250, ISLC 250, lSWB 200, ISMC 225, ISLC 225, ISLB 225, ISMB 200, ISHB 150, ISHB 150, ISHB 150, lSMC 200, ISLC 200, lSWB 175, lSLB 200, ISMB 175, ISMC 175, ISLC 175, lSLB 175, ISJB 225, ISJC 200, ISWB 150, , Weight per, Metre, , Sectional, Area, , Depth of Section, , Width of, Flange, , Thickness of, Flange, , Thickness of, Web, , (D), , ( b,), , (t,), , (tw), , Section, Modulus, , Radii of Gyration, , A, f (rz), , (r,)’, , Plastic, Modulus, , (Zez), , (-%), , kg/m, , cm2, , mm, , mm, , mm, , mm, , cm, , cm, , cm], , cm3, , (2), , (3), , (4), , (5), , (6), , (7), , (8), , (9), , (lo), , (11), , 64.96, 53.66, 56.26, 49.47, 48.08, 59.66, 52.05, 54.94, 45.64, 47.55, 42.11, 42.02, 50.94, 47.54, 43.24, 38.67, 39.72, 35.53, 35.65, 36.71, 33.01, 30.53, 29.92, 32.33, 44.08, 38.98, 34.48, 28.21, 26.22, 28.11, 25.27, 24.62, 24.38, 22.40, 21.30, 16.28, 17.8, 21.67, , ~50, 350, 300, 350, 300, 225, 250, 225, 300, 250, 300, 275, 200, 200, 225, 250, 225, 250, 250, 200, 225, 225, 225, 200, 150, 150, 150, 200, 200, 175, 200, 175, 175, 175, 175, 225, 200, 150, , 250, 100, 140, 100, 150, 225, 200, 225, 90, 125, 100, 140, 200, 200, 150, 80, 110, 125, 100, 140, 80, 90, 100, 100, 150, 150, 150, 75, 75, 125, 100, 90, 75, 75, 90, 80, 70, 100, , 51.0, *42. 1, *44.2, *38.8, *37.7, 46.8, 40.9, 43.1, *35.8, 37.3, *33.1, *33.O, 40.0, 37.3, 33.9, *30.4, 31.2, *27.9, 28.0, 28.8, *25.9, *24.O, *23.5, 25.4, 34.6, 30.6, 27.1, *22. 1, *20.6, 22.1, *19.8, *19.3, ●19.1, *17.6, *16.7, ●12.8, 13.9, 17.0, , 9.7, 13.5, 12.4, 12.5, 9.4, 9.1, 9.0, 9.1, 13.6, 12.5, 11.6, 8.8, 9.0, 9.0, 9.9, 14.1, 11.8, 8.2, 10.7, 9.0, 12.4, 10.2, 8.6, 10.8, 9.0, 9.0, 9.0, 11.4, 10.8, 7.4, 7.3, 8.6, 10.2, 9.5, 6.9, 5.0, 7.1, 7.0, , 6.9, 8.1, 7.5, 7.4, 6.7, 8.6, 6.7, 6.5, 7.6, 6.9, 6.7, 6.4, 7.8, 6.1, 6.4, 7,1, 6.5, 6.1, 6.1, 6.1, 6.4, 5.8, 5.8, 5.7, 11.8, 8.4, 5.4, 6.1, 5.5, 5.8, 5.4, 5.5, 5.7, 5.1, 5.1, 3.7, 4.1, 5.4, , 10.91, 13.66, 12.37, 13.72, 12.35, 9.58, 10.69, 9.80, 11.81, 10.39, 1I .98, 11.31, 8.55, 8.71, 9.52, 9.94, 9.31, 10.23, 10.17, 8.46, 9.03, 9.14, 9.15, 8.32, 6.09, 6.29, 6.50, 8.03, 8.11, 7.33, 8.19, 7.19, 7.08, 7.16, 7.17, 8.97, 8.08, 6.22, , 5.49, 2.83, 2.84, 2.82, 2.80, 4.84, 4.06, 4.96, 2.61, 2.65, 2.87, 2.61, 4.42, 4.51, 3.22, 2.38, 2.34, 2.33, 2.89, 2.99, 2.38, 2.62, 1.94, 2.15, 3.35, 3.44, 3.54, 2.23, 2.37, 2.59, 2.13, 1.86, 2.23, 2.38, 1.93, 1.58, 2.18, 2.09, , 618.9, 571.9, 573.6, 532.1, 488.9, 487.0, 475.4, 469.3, 424.2, 410.5, 403.2, 392.4, 372.2, 360.8, 348.5, 305.3, 305.9, 297.4, 295.0, 262.5, 239.5, 226.5, 222.4, 223.5, 218.1, 205.3, 194.1, 181.9, 172.6, 172.5, 169.7, 145.4, 139.8, 131.3, 125.3, 116.3, 116.1, 111.9, , 678.73, 672.19, 651.74, 622.95, 554.32, 542.22, 527.57, 515.82, 496.77, 465.71, 466.73, 443.09, 414.23, 397.23, 389.93, 356.72, 348.27, 338.69, 338.11, 293.99, 277’.93, 260.13, 254.72, 253.86, 251.64, 232.52, 215.64, 211.25, 198.77, 194.20, 184.34, 166.08, 161.65, 150.36, 143.30, 134.15, 133.12, 126.86, , Shape Factor, , (zpz/ Zez), , (12), 1.0967, , 1.1754, 1.1362, i.1707, 1.1338, 1.1134, 1.1097, 1.0987, 1.1711, 1.1345, 1.1576, 1.1305, 1.1129, 1.1010, 1.1189, 1.1684, 1.1385, 1.1388, 1.1462, 1.1200, 1.1605, 1.1485, 1.1453, 1.1358, 1.1538, 1.1326, 1.1110, 1.1614, 1.1516, 1.1258, 1.1370, 1.1422, 1.1563, 1.1452, 1.1437, 1.1535, 1.1465, 1.1337

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Table 46 (Concluded), Designation, , (1), ISMC 150, , z, , 0, , ISMB 150, ISLC 150, ISLB 150, ISJC 175, ISJB 200, ISMB 125, ISMC 125, ISLB 125, ISJC 150, ISLC 125, ISJB 175, ISMB 100, ISJB 150, ISJC 125, ISMC 100, ISLB 100, ISLC 100, ISJC 100, ISMC 75, , ISLB 75, ISLC 75, NOTE —, , Weight per, , Sectional, , Metre, , Area, , Depth of Section, , Radii of Gyration, , Width of, , Thickness of, , Thickness of, , Flange, , Flange, , Web, , (D), , ( b,), , (?,), , (tw), , f (r,), , Section, Modulus, , A, , (r,)’, , Plastic, , Shape Factor, , Modulus, , (ZJ, , (%), , N, , (zpz/za), , kg/m, , ~m2, , mm, , mm, , mm, , mm, , cm, , cm, , cm’, , cm], , (2), , (3), , (4), , (5), , (6), , (7), , (8), , (9), , (10), , (11), , (12), , 5.4, 4.8, 4.8, 4.8, 3.6, 3.4, 4.4, 5.0, 4.4, 3.6, 4.4, 3.0, 4,2, , 2.21, 1.66, 2.37, 1.75, 1.88, 1.17, 1.62, 1.92, 1.69, 1.73, 2.05, 0.97, 1.05, 1.01, , 1.12, 1.57, 1.42, 1.21, , 103.9, 96.9, 93.0, 91.8, 82.3, 78.1, 71.8, 66.6, 65.1, 62.8, 57.1, 54.8, 36.6, 42.9, 43.2, 37.3, 33.6, 32.9, 24.8, 20.8, , 1.14, 1.26, , 19.4, 17.6, , 119.82, 110.48, 106.17, 104.50, 94.22, 90.89, 81.85, 77.15, 73.93, 72.04, 65.45, 64.22, 41.68, 49.57, 49.08, 43.83, 38.89, 38.09, 28.38, 24.17, 22.35, 20.61, , 1.1533, 1.1401, 1.1416, 1.1384, 1.1449, 1.1639, 1.1399, 1.1585, 1.1356, 1.1472, 1.1462, 1.1799, 1.1389, 1.1556, 1.1362, 1.1750, 1.1573, 1.1576, 1.1442, 1.1904, 1.1522, 1.1710, , 16.4, 14.9, 14.4, 14.2, ●11.2, *9.9, 13.0, 12.7, 11.9, 9.9, 10.7, *8.1, 8.9, *7.1, 7.9, 9.2, 8.0, 7.9, *5.8, 6.8, , 6.1, *5.7, Sections having ‘weight, , 10.21, 10.02, 7.41, 8.67, , 150, 150, 150, 150, 175, 200, 125, 125, 125, 150, 125, 175, 100, 150, 125, 100, 100, I 00, 100, 75, , 75, 80, 75, 80, 60, 60, 75, 65, 75, 55, 65, 50, 50, 50, 50, 50, 50, 50, 45, 40, , 9.0, 7.6, 7.8, 6.8, 6.9, 5.0, 7.6, 8.1, 6.5, 6.9, 6.6, 4.6, 7.0, 4.6, 6.6, 7.5, 6.4, 6.4, 5.1, 7.3, , 3.0, 3.0, 4.7, 4.0, 4.0, 3.0, 4.4, , 6.11, 6.18, 6.16, 6.17, 7.11, 7.86, 5.20, 5.07, 5.19, 6.9, 5.11, 6.83, 4.00, 5.98, 5.18, 4.00, 4.06, 4.06, 4.09, 2.96, , 7.71, 7.26, , 75, 75, , 50, 40, , 5.0, 6.0, , 3.7, 3.7, , 3.07, 3.02, , 20.88, 19.00, 18.36, 18.08, 14.24, 12.64, 16.60, 16.19, 15.12, 12.65, 13.67, 10.28, 11.4, 9.01, 10.07, , 11.70, , per meter’markedwith an asterik(*) may, , be chosen, , as the section, , is lighter, , having, , 1.60, , 1.49, , high ZP as compared to sections below it., , 3, Oe, o, o, .., o, o, +

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