持荷状态下大尺度钢管拱肋拼接焊缝焊接残余应力分析  

Analysis of Residual Stress in Welding Joints of Large-Scale Steel Tube Arch Rib Under Sustained Load Condition

作　　者：韩玉 严仁章[2] 陈西洋 罗小斌 秦大燕 HAN Yu;YAN Ren-zhang;CHEN Xi-yang;LUO Xiao-bin;QIN Da-yan(Guangxi Road and Bridge Engineering Group Co.,Ltd.,Nanning 530200,China;School of Civil Engineering,Chongqing Jiaotong University,Chongqing 400074,China)

机构地区：[1]广西路桥工程集团有限公司,广西南宁530200 [2]重庆交通大学土木工程学院,重庆400074

出　　处：《桥梁建设》2022年第4期74-81,共8页Bridge Construction

基　　金：中央引导地方科技发展专项(桂科ZY20111020);广西重点研发计划(桂科AB17292018);重庆市自然科学基金面上项目(cstc2020jcyj-msxmX0089)。

摘　　要：为研究持荷作用对大尺度钢管拱肋拼接焊缝残余应力的影响,以及大尺度焊缝焊接残余应力的分布规律,以主跨575 m的特大跨钢管混凝土拱桥--广西平南三桥为背景进行分析。开展持荷状态下拱肋拼接焊缝残余应力足尺模型试验与数值模拟,分析拱肋拼接焊缝试件轴向、环向焊接残余应力分布情况,并与非持荷状态试件进行对比。结果表明:持荷作用对钢管拱肋拼接焊缝焊接残余应力的影响较小,但管内节点处肋板的设置会对钢管拱肋拼接焊缝残余应力产生较大影响;拼接节点处的轴向焊接残余应力以拉应力为主,沿拱肋主管轴向先增大后减小,最终趋于稳定;拼接节点处的环向焊接残余应力沿主管环向拉-压交替分布,拉应力分布在离焊缝较近区域与肋板影响区域,压应力主要分布在肋板之间区域。The Third Pingnan Bridge in Guangxi Province,which is a concrete-filled steel tube arch bridge with a main span of 575 m,is used as a case to study the effect of sustained load on the residual stress in the welding joints of large-scale concrete-filled steel tube arch rib and the distribution of residual stress.Full-scale model test and numerical simulation were conducted to examine the residual stress in the welding joints of arch rib under sustained load condition,and analyze the distribution characteristics of the axial and circular welding residual stresses in the specimen,furthermore,the findings were compared with the specimen without sustained load.The results show that the effect of sustained load on the residual stress in the welding joints of the steel tube arch is minor,but the influence of stiffening plates arrangement at assembly nodes inside the steel tube is significant.Tensile stress is the dominant axial residual stress at the assembly nodes,which reversed after an increase along the z-axis of chord tubes of the arch rib,and eventually stabilized.At the assembly nodes,the tensile and compressive circular residual stresses were alternately distributed,looping the chord tubes of the arch rib,the tensile stress exists in the zone close to welding joints and the influential zone of the stiffening plates,while the compressive stress mainly concentrates in the zones between stiffening plates.

关 键 词：钢管混凝土拱桥 拱肋拼接焊缝 大尺度焊缝 持荷状态 焊接残余应力 足尺模型试验 数值模拟 

分 类 号：U448.22[建筑科学—桥梁与隧道工程] U441.5[交通运输工程—道路与铁道工程]