钢桥对接焊缝残余应力及变形场数值分析与试验验证

摘要

为研究钢桥对接接头焊接残余应力及变形场的分布规律,基于ABAQUS软件建立16 mm厚Q345qD钢板多层对接焊三维有限元模型,对焊接残余应力及变形场进行模拟预测,并对模拟结果进行试验验证.结果表明焊接残余应力和变形的数值模拟结果与试验实测值吻合较好.对接接头纵向焊接残余应力沿垂直于焊缝方向成拉-压分布状态,其最大值位于热影响区,约为350 MPa,接近材料的屈服强度;纵向残余应力在距焊缝中心60 mm范围内为拉应力.横向焊接残余应力的应力水平相对较低,最大值约为100 MPa.焊接变形主要以平面外变形为主,变形模式为马鞍形,最大变形值发生在试板中部远离焊缝中心的外边缘.%In order to study the distribution of welding residual stress and deformation for butt weld in steel bridge,based on the ABAQUS software,a three-dimensional finite element model was established on the mul-tilayer butt welding of the 16 mm thick Q345qD steel plate,to simulate the welding residual stress and deform-ation fields and to verify the simulation results.The results indicate that the simulation values of the welding residual stress and deformation are in good agreement with the experimental data.In butt weld plate,the weld-ing longitudinal residual stress exhibits tension-compression distribution along the path perpendicular to the weld line.Its peak value is about 350 MPa,which is close to the yield strength of the material and is located in the heat affected zone.The longitudinal residual stress is tensile stress in the range of 60 mm from the weld center.The value of transverse residual stress is small,and its maximum value is about 100 MPa.The welding deformation is mainly dominated by out-of-plane distortion,and the typical deformation mode is of saddle shape.Meanwhile,the maximum out-of-plane distortion is found at the outer edge of test plate center,away from the weld center.