Investigation into welding residual stress of high-performance-steel Q500qE welded-joint

Abstract

This study investigates the welding residual stress (WRS) spatial distribution in a high-performance steel (HPS) Q500qE unequal-thickness butt-welded joint of steel bridge tower. The hole-drilling and contour methods were used to measure the initial residual stress (IRS) of the base material and WRS in the welded joint. Additionally, the welding process was simulated using ABAQUS, incorporating IRS of base material to study WRS of welded joint. The comparison between measured and simulated WRS showed good agreement, validating the simulation's effectiveness and accuracy. The results reveal that simulated longitudinal and transverse WRSs (LWRS and TWRS) on the top and bottom surfaces indicate high tensile stresses in the weld region, exceeding the measured yield strength of the Q500qE steel. These stresses decrease and transition to compressive states as the distance from the weld increases. LWRS contours show a high tensile stress region along the plate thickness in the weld. Away from the weld, the LWRS is compressive at the surface layer and tensile in the interior zone, especially in the 56 mm-thick base material. The simulated TWRS shows high tensile stress primarily at the weld surface layer, with compressive stress mainly in the surface layer of the 56 mm-thick base material. Compared to vertical WRS (VWRS), the simulated LWRS and TWRS with IRS show higher stress levels and significant stress gradients.