Experimental investigation of Σ-section channel steel with complex edge stiffeners and web holes under axial compression

The axial bearing capacity of thin-walled steel members with web holes and different section shapes are investigated. Ten simply supported compression members with two types of complicated sections, including channels with complex edge stiffeners and web holes, channels with complex edge stiffeners and Σ type web stiffeners and web holes, were tested. Results show that the axial compression loading efficiency of the Σ-section specimens with web holes can increase about 30% to 50% compared with channels with complex edge stiffeners and web holes under the same conditions. Compared with the specimens without holes, there is no change in failure modes, but the failure positions are near to the holes. Finite Element Analysis (FEA) is carried out to simulate the compression tests. FEA results agree well with the experimental data. Based on this, the load carrying efficiency and Von Mises stress distribution of channel columns with web holes are compared with those without holes by FEA. It is shown that the carrying efficiency of Σ-section models with holes decreases by 25.7% compared with the same section models without holes, while the model of channel section with complex edge stiffeners and holes decreases by 6.15% in average. Because of the perforations on the web, the positions of the stress concentration and the maximum stress change from the webs near the mid-height of the models to the locations adjacent to the holes. ©, 2015, Editorial Board of Jilin University. All right reserved.