Post-local buckling of steel plates in concrete-filled thin-walled steel tubular columns under biaxial loading

摘要

This paper studies the post-local buckling behaviour of steel plates in concrete-filled thin-walled steel tubular columns under biaxial loading using the finite element method. Geometric and material nonlinear finite element analyses are undertaken to investigate the post-local buckling strengths of imperfect steel plates under stress gradients. Based on the results obtained from the nonlinear finite element analyses, a set of effective width formulas are proposed for determining the ultimate strengths of steel plates in concrete-filled steel tubular columns. The proposed effective width formulas are verified by comparisons with formulas developed by other researchers and can be used directly in the design of steel plates in concrete-filled steel tubular beam-columns.