Inelastic Post‐Buckling Behavior of Tubular Struts

Abstract

A numerical procedure for tracing the inelastic post‐buckling load‐deflection path of tubular struts is proposed. The analysis accounts simultaneously for both the geometrical and material nonlinearities with special emphasis placed on the influence of strain‐unloading. An iterative numerical arc‐length technique is employed in the solution procedure, but once strain‐unloading is detected, iterations are suppressed and the procedure converted to a pure incremental method with arc‐length constraint only. Predictions of the maximum loads and of the post‐buckling load‐deflection paths using the proposed approach compared very well with other published analytical results and with tests. The approach is simple and may be applied to general thin‐walled cross sections and to include cyclic loading.