BEHAVIOUR OF CYLINDRICAL SHELLS UNDER WIND LOAD

Abstract

Tvlvs yodels with cylindrical curved roofs, and two models with pitched root have been tested In wind tunnel to ' determine the wind pressure distribution on such surfaces. The effect of various paras.tere (via. S.si' oentral angle, radium of shell., height of supporting walls, size and position of openings) on the wind pressure distribution has also been studied* It has been shown that the approach of Indian and British codes of prescribing the wind pressure coefficients on cylindrical surfaces, corresponding to the slop* of the *horde is quite inadequate„ In general the provisions of the various codes are quit. inadequate for design purposes. The modified recommendations for determining the wind load including the effect of permeability on it have been given. A general computer program has been developed to analyze the shells for any Irregular loading by replacing it into a series of iquivalent lint loads# Three shells, one each lying in the category of long,, intermediate and short s lls have been analysed# The results have been presented for the first two types, while for the short shell desired accuracy could not be obtained due to large round off errors and small also of the available computer (X M16ao), For Indeterminate shells an1l.7nie was carried for actual as well an idealised wind load* Zt has been shown that the results obtained for the two eases are almost the same for all prat tidal purposes. H ►nae , the reoousnd•d idealised wind to d is suffiotent for the .design purpose