EXPERIMENTAL INVESTIGATION ON CHANNEL COLUMNS WITH COMPLEX EDGE STIFFENERS AND INTERMEDIATE STIFFENERS UNDER AXIAL COMPRESSION

A total of 16 pin-ended cold-formed steel columns were tested; these columns were with four types of complicated sections including: channels with complex edge stiffeners, channels with complex edge stiffeners and intermediate V type stiffeners in the web, channels with complex edge stiffeners and intermediate V type stiffeners in the web and the flanges. The ultimate load-carrying capacity and deformation behavior of cold-formed steel members with complicated cross sections were studied in this paper. It was found that ultimate load-carrying capacity of members under axial compression increased markedly because the element width-to-thickness ratio was reduced effectively by using intermediate V type stiffeners. Comparing with channels with complex edge stiffeners under same conditions, the axial compression loading efficiency of members with intermediate stiffeners increased about 10% to 30%. Tests were simulated by finite element analysis (FEA). The analysis results agreed well with experimental data. FEA was verified by experimental results. Based on it, the ultimate load-carrying capacity of channel columns with complex edge stiffeners were compared with lipped channel columns under axial compression. The results indicate that loading efficiency of channel columns with complex edge stiffeners is higher than lipped channel columns.