Longitudinal residual stress distribution of Q460 high-strength steel welded T-section

Longitudinal residual stress is one of the main factors affecting the ultimate bearing capacity of steel compression members. Firstly, the longitudinal residual stress distribution of four Q460 high-strength steel welded T-sections was measured using the sectioning method. Secondly, a thermal-structural coupling analysis method was used in general finite element program ANSYS to simulate the cutting and welding processes of the steel plates. The numerical results of longitudinal residual stress were then compared with experimental values to verify the correctness of the finite element analysis process. Furthermore, based on the finite element method, longitudinal residual stress distributions of Q460 high-strength steel welded T-sections with different cross-sectional dimensions were obtained, and a summary analysis was conducted to study the effects of the width-thickness ratio and thickness on the magnitude and distribution of residual stress. The results show that the tensile residual stress is distributed in the area around the weld, the outer extension of the flange and web, while the compressive residual stress is distributed in the middle part of the outer extension of the flange and web. Moreover, the tensile residual stress is independent of the width-thickness ratio and the plate thickness, while the compressive residual stress is inversely proportional to the width-thickness ratio and plate thickness. The residual stress in the flange and web is accord with the self-equilibrium condition. According to the above analysis, a longitudinal residual stress distribution model for Q460 high-strength steel welded T-section is proposed, which can be used for the subsequent numerical analysis of the overall stability and bearing capacity of steel compression members.