Buckling Modes of Cold-Formed Thin-Walled Steel Beams Under Different Impact Positions

This paper aims to study the buckling mode of cold-formed thin-walled channel steel beams under different impact positions. The impact test of the thin-walled channel steel beams was carried out using a drop hammer to obtain the acceleration of the measuring point and the buckling mode of the member. The experimental results and ANSYS/LS-DYNA numerical simulation results are compared and analyzed. The results show that the acceleration curve change trend obtained from the test is similar to numerical simulation. The difference between the acceleration obtained by numerical simulation and the maximum value obtained by test accounts for 5.86% of the simulated value. Therefore, the dynamic response results of cold-formed thin-walled channel steel beams under numerical simulation can be effectively verified by the test. Numerical simulation methods are used to analyze the dynamic response of two groups of members under impact at different positions and the corresponding buckling modes. The results show that the buckling of the members at 1/2, 1/3, and 1/4 of the flange of the impact member is similar to the O-I mode under the same conditions. The buckling mode is half-O mode when the midpoint of the intersection line between flange and web is impacted. The buckling mode is U-shaped when the midpoint of the intersection line between flange and the curling edge is impact.