Abstract
Residual stress significantly affects the structural safety of steel bridge decks. This study investigates the influence of key geometric parameters, including top plate thickness, bevel angle, and the height and thickness of U ribs, on welding-induced residual stress through numerical simulation. First, in ABAQUS, the welding heat source is applied to the weld seam using the “life and death” element technique and a Dflux subroutine to obtain the temperature field. Next, the temperature field data are applied as external loads in a coupled stress field analysis to characterize the residual stress distribution, with parametric modeling used to examine the effects of varying geometric parameters. Finally, regression analysis using SPSS identifies the sensitivity of each parameter. The results show that increasing the top plate thickness reduces the maximum tensile stress near the weld but has little effect on residual stress in regions distant from the weld; increasing the bevel angle from 46° to 52° raises the peak longitudinal residual stress from 455 MPa to 520 MPa, although this effect decreases with distance from the weld; increasing U rib height reduces peak stress at the weld, while thicker U ribs result in a more uniform stress distribution. Regression analysis confirms that top plate thickness and bevel angle are the most influential factors affecting residual stress. These findings provide a quantitative basis for optimizing the design and welding process of steel bridge deck U rib structures.