Welding Residual Stress Distribution and Experimental Verification of Corrugated Steel Web Girders

To study the distribution law of welding residual stress of corrugated steel web girders, a three-dimensional thermo-elastoplastic model was established by finite element software, and the welding temperature field and stress field were numerically simulated by the finite element method using thermal and mechanical coupling analysis technology. Double ellipsoidal heat source and modified element material properties were used for energy input and weld filling, respectively. The simulation results were compared with the measured values. The results show that the residual stress distribution of corrugated steel web girders predicted by the finite element method has the same trend as the measured values. At the bending angle of the weld of the corrugated steel web girder, the residual stress fluctuates continuously in a certain range. The peak value of the residual stress in the bottom plate and web appears in the central area of the weld, which is 1.30 times and 1.26 times the yield strength of the material. respectively. The longitudinal residual tensile stress of the bottom plate decreases rapidly within 78 mm on both sides of the weld centerline and then slowly transitions to compressive stress. In addition, the compressive stress on the narrow side of the bottom plate increases linearly, and the maximum value is about 0.61 times the yield strength of the material. The compressive stress decreases linearly on the wider side of the bottom plate and is converted to the tensile stress at the edge. The analysis indicates that the welding speed has little effect on the residual stress distribution but has a significant effect on the peak value of residual stress. When the welding speed increases from 150 mm/min to 250 mm/min, the maximum residual stress in transverse and longitudinal directions increases by 27.11% and 5.88%, respectively.