Buckling behaviour of thin-walled aluminium and stainless steel columns using Generalised Beam Theory

摘要

A modification/extension of the available (isotropic) Generalised Beam Theory (GBT) is presented, which enables its application to study the buckling behaviour of thin-walled columns made of non-linear elastic-plastic materials, such as aluminium or stainless steel alloys. In particular, attention is focused on describing and discussing the specific modifications that must be incorporated in the usual GBT procedure to handle non-linear materials. Next, since GBT includes genuine folded-plate theory concepts, some attention is devoted to the evaluation of the adequate instantaneous elastic moduli, an issue that involves the choice of a set of flow and strain-hardening rules and has implications on the GBT procedure. Finally, in order to validate and illustrate the application and capabilities of the proposed non-linear GBT, some numerical results are presented and discussed. They concern uniformly compressed rectangular plates and lipped channel columns and the material behaviour is described by the J_2 flow theory of plasticity.