Influence of Welding Effect in Different Welding Conditions on Stiffened Wallboards of Prefabricated Box-Plate Steel Structures

The welding simulations of Q235B and Q345B steel plates was conducted by ABAQUS associated DFLUX heat source subroutine, and the welding residual stress test of steel sheets was conducted by ultrasonic detection method. It was found that tensile stress was the main longitudinal residual stress in the heat-affected zone of the weld, and there was tensile stress and compressive stress in the transverse residual stress in the whole welding specimens. The test results were basically consistent with the simulation results, which verified the reliability of simulating welding of steel sheets. Using the same simulation method, the welding process of stiffened steel wallboards was simulated, and the residual stress, welding deformation, and shear capacity were analyzed. The results showed that the welding residual stress and welding deformation of the stiffened steel wallboard mainly occurred at the welding seam between the stiffening rib and the wallboard, and the residual stress along the welding seam direction was small at the upper and lower ends and large in the middle. The influence of discontinuous welding on high residual stress and overall residual deformation of stiffened steel wallboards was obviously lower than that of continuous welding. In all welding conditions, the minimum ultimate shear capacity decreased by 6.8% compared with the maximum ultimate shear capacity. After comparing all working conditions, it was found that the welding condition with a larger discontinuity distance had a better effect.