Study on Tensile Properties of Q235B / Q345qE Dissimilar Steel T-joints

As a key component of steel structure bridges, the performance of welded joints directly affects the safety and reliability of the whole structure. Especially under complex load conditions, welded joints are easy to become the leading area of structural failure. Therefore, it is necessary to simulate the tensile fracture of welded joints, which is an important means to ensure the safety and reliability of the structure. The T-joint is more complex and representative than the butt joint in the manufacturing process. In this study, the finite element simulation of welding was carried out on the analysis model. Based on the stress field obtained by welding simulation, the tensile fracture simulation was carried out based on Johnson-Cook (J-C) damage criterion, and the tensile strength and fracture position of the joint were obtained. The results show that the residual stress generated by welding is mainly concentrated in the weld seam, and the residual stress of the weldment will be reduced to a certain extent after a long period of cooling. The tensile fracture results show that the stress of the weldment will be concentrated near the weld during the tensile process. The error between the simulated tensile strength of the T-joint and the test is only 1.54 %, and the fracture position of the analysis model is also basically consistent with the test results. The research provides a feasible basis for the application of dissimilar steel welding technology in the field of bridge engineering.