Research on the local-distortional interaction buckling capacity of stainless steel lipped C-section columns

The plates of the specimens subjected to a large section width to thickness ratio are prone to multiple instances of mode interaction buckling failure under compression. Hence, to investigate the local-distortional interaction buckling capacity of stainless steel lipped C-section columns, the material properties test of 4 stainless steel plate specimens and the capacity tests of 19 stainless steel lipped C-section column specimens under axial compression were carried out. The development process and failure mode of the local-distortional interaction buckling of stainless steel columns were revealed, and the local-distortional interaction buckling capacities, load-axial shortening curves, load-lateral displacement curves and load–strain curves of the stainless steel columns were obtained. The numerical analysis model of the stainless steel lipped C-section column under compression was established based on ABAQUS finite element software. The finite element results were in agreement with the test results, which verified the accuracy of the finite element model. A parametric analysis was carried out on two key factors, the initial geometric imperfection amplitude and boundary conditions, which affect the local-distortional interaction buckling capacity of stainless steel lipped C-section columns. The results show that the initial geometric imperfection amplitude of specimen has a significant influence on the local-distortional interaction buckling capacity of stainless steel lipped C-section column, while the influence of boundary conditions is small.