Elasto-plastic analysis of box-beam-columns including local buckling effects

A nonlinear finite element procedure for the pre- and postbuckling analysis of thin-walled box-section beam-columns is presented. The influence of local plate buckling upon the overall ultimate buckling behavior of the member is incorporated in the analysis by adopting a set of modified-stress-versus-strain curves for axially loaded plates. Factors such as residual stresses, associated with hotrolled and cold-formed sections, and initial geometrical imperfections are accounted for in the analysis. A number of examples are presented to demonstrate the accuracy and efficiency of the method