Effects of member buckling and yielding on ultimate strengths of space trusses

Abstract

Space trusses represent one type of structure whose ultimate loading capacity cannot be solely determined from linear analysis. In comparison with the large amount of research on the geometric nonlinear behaviours of space trusses, relatively little work has been conducted on the effects of member buckling and yielding. In this study, constitutive laws that consider these effects are first derived for a hinged bar. Such constitutive laws are then included in an incremental-iterative procedure for tracing the postbuckling responses of space trusses, based on a rigorous, updated, Lagrangian formulation. From the numerical studies, it is concluded that the buckling of individual members can result in drastic reduction of the ultimate loading capacity of space trusses. The effect of member yielding, however, tends to affect the duration of the elastic range in the postcritical stage for most structural steels. Copyright © 1996 Elsevier Science Ltd.