Residual stress of 460 MPa high strength steel welded box section: Experimental investigation and modeling

An experimental study is presented to investigate and model the residual stress in 460 MPa high strength steel welded box sections using the sectioning method. A total of six square box sections with various width-thickness ratios and thicknesses of steel plates were tested and over 2000 original readings were obtained to quantify the magnitude and distribution of both compressive and tensile residual stresses. The effects of width-thickness ratio and plate thickness on residual stresses, the human error and interaction of the four component plates were clarified. The compressive residual stress magnitude was found to be significantly correlated with the sectional dimensions; while for the tensile stresses near the weld region no clear correlation was found. The human error obtained through the comparison of experimental results measured by two persons for the same section was quite small. No residual stress interaction among four component plates was identified due to the residual stress equilibrium within each plate. Finally, a distribution model and its simplified form were established in this study, and a good agreement was found in the comparison with experimental results.