Research on distortional buckling capacity of stainless steel lipped C-section beams

Abstract

Stainless steel lipped C-section components have complex nonlinear buckling behaviour, and the relevant calculation theories need to be improved. Therefore, based on experiments on the distortional buckling capacity of 8 stainless steel lipped C-section beams, a finite element model is established using the ABAQUS software, and the accuracy of the model is verified. Then, a series of parametric analyses are carried out, focusing on the influences of cold working, initial geometric imperfection and distortional buckling slenderness. Next, a further parametric analysis of the distortional buckling slenderness of stainless steel beams is conducted using the finite strip program CUFSM, and the effects of geometric parameters (section height, flange width, lip width and thickness) and the coupling between different parameters on the distortional buckling slenderness are analysed. A simplified formula of the critical stress of elastic distortional buckling for stainless steel lipped C-section beams is proposed and its accuracy is verified. Finally, based on the direct strength method, taking the full section plastic moment as the reference bearing capacity, a calculation formula of the distortional buckling bearing capacity is proposed. The results of the formula are compared with the experimental results, which proves that the formula can accurately predict the distortional buckling bearing capacity of stainless steel lipped C-section beams.