GBT-based semi-analytical solutions for the elastic/plastic stability analysis of stainless steel thin-walled columns exposed to fire

The authors gratefully acknowledge the financial support of FCT (Fundação para a Ciência e a Tecnologia, Portugal), through Project “StaSteFi—Fire design of stainless steel structural elements”. ; This paper presents and illustrates the application of an efficient Generalized Beam Theory (GBT) semi-analytical solution procedure to determine elastic and plastic bifurcation loads (linear stability analysis) of stainless steel thin-walled members subjected to uniform compression and exposed to fire. Besides global (flexural or flexural-torsional) buckling, the proposed GBT formulation allows for cross-section deformation and therefore makes it possible to capture local and distortional buckling. The temperature effect is taken into account using the material law for stainless steel specified in Eurocode 3 part 1-4 (CEN 2006) and Annex C of part 1-2 (CEN 2009). For plastic buckling, the material tangent moduli are obtained using both J2 small-strain incremental and deformation plasticity theories. For illustrative purposes, the procedure is applied to columns with a lipped channel cross-section. ; authorsversion ; published