Study on Residual Stress Relief of Welded Structural Steel Joints

Abstract

This paper presents the results obtained from the residual stress relief tests on 21 welded structural steel joints: 17 butt‐welded, two tee, and two corner joint specimens. The A572 grade 50 structural steel plates of two different thicknesses, 15 and 32 mm, were used. All specimens were welded by the submerged arc welding (SAW) process and were designed according to the prequalified welded joints specified by the American Welding Society. In this study, a controlled low‐temperature stress‐relief method was used for residual stress relief. The experimental results show that by using an appropriate combination of the heating temperature, heating distance, and cooling method, the original high‐tensile residual stresses near the weld of the joint can be reduced effectively. The residual stresses before and after the heat treatment were measured by using the blind hole‐drilling method. A reduction of more than 50% of the original tensile residual stresses adjacent to the weld was observed.