Interactive Buckling in Thin‐Walled Beam‐Columns

Abstract

A new analytical model has been developed for a study of the response of thin‐walled beam‐columns having doubly symmetric cross sections. The novel features of the model are that: (1) It incorporates the interaction of overall buckling/bending with two companion local modes; (2) it accounts for the phenomenon of amplitude modulation; and (3) it can model any set of realistic end conditions. These features are a result of an innovative combination of the finite strip and finite element techniques. The model has been tested for numerical convergence and against the available results on square box columns. A small number of examples have been studied. These relate to the performance of eccentrically loaded columns and single story frames. Also, the vital necessity of considering amplitude modulation in thin‐walled beam columns has been brought out.