SP 64 (S & T) : 2001 Explanatory Handbook on Indian Standard Code of Practice for Design Loads (Other than Earthquake) for Buildings and Structures

Scope

The aim of this Handbook is to provide detailed backgroundinformation on the provisions of IS 875 : Part 3 : 1987 and the useof the standard for estimating wind loads on structures. Theemphasis has been on the identification of source material used,philosophical ideas behind the changes in 1987 edition and guidanceto the use of the standard. Clauses 0.1 and 0.2 of this Handbookcontains background information, philosophical ideas, nature ofwind and wind effects on structures. Clause 0.3 brings out theshortfalls of the earlier standard (IS 875 : 1964), vis-a-vis windzoning, risk level, wind velocity and its variation with height,dynamic analysis, effect of structure size and shape. Clause 2explains the various terminology used in the standard. Clause 3discusses the main features of the revised Code like new windzoning map, estimation of design wind speed, concept of returnperiod, effects of terrain roughness and structure size, localtopography, correct velocity-pressure relationship. In Clause 4wind pressure and forces on buildings/structures are discussed inlight of pressure coefficient method. Details of force coefficientmethod are given in 4.3 while dynamic effects like along-wind andacross-wind responses are explained in 5 and 6. Requirements ofwind tunnel studies are detailed in 7. Clause 8 conducts the userto the various provisions of the standard with the help of flowdiagrams. Clause 9 contains the methodology for the estimation ofwind loads on low rise buildings, with the help of examples. Clause9.3 is devoted to the estimation of dynamic effects of wind usinggust factor method and contains typical solved examples ofstructures.

Note - All Clauses, Figures and Tables in Square Brackets in theHandbook Refer to Clause Numbers, Figure Numbers and Table Numbersof IS 875 : Part 3 : 1987, respectively.