冷弯薄壁G形钢双肢开口截面拼合柱轴压性能试验研究

In order to investigate the axial compression behavior of cold-formed G-shaped steel double-limbs built-up open-section column, axial compressive experiments of 30 built-up specimens were presented. The main design parameters of specimens were the slenderness ratio and the ratio of web height to thickness. The failure modes, relationships between axial load and deformation and the effects of cross section dimensions on the bearing capacities of the spExperimental study on behavior of cold-formed G-shaped steel double-limbsecimens were investigated. It is demonstrated that the primary buckling modes of the specimens involved local buckling and overall buckling．With the increase of specimen length, buckling mode was changed from local buckling to overall buckling. The enhancement of the ratio of web height to thickness could enhance the bearing capacities．The axial load capacities of the specimens were calculated according to the domestic and oversea design codes. The comparison between the calculations and experimental data indicates that the formulas are unconservative. The codes CSA S136 are modified and a formula for calculating the bearing capacity of cold-formed G-shaped steel double-limbs built-up open-section columns under axial compression is presented through regression analysis of the test datas. The formula is valuable for engineering design.