波形钢腹板梁焊接残余应力分布及试验验证  

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

作　　者：冀伟[1,2] 刘勇[2] JI Wei;LIU Yong(College of Civil Engineering,Hunan University,Changsha 410082,China;College of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China)

机构地区：[1]湖南大学土木工程学院,湖南长沙410082 [2]兰州交通大学土木工程学院,甘肃兰州730070

出　　处：《西南交通大学学报》2024年第2期289-297,共9页Journal of Southwest Jiaotong University

基　　金：国家自然科学基金(52168019,51868039);甘肃省重点研发计划(23YFGA0043);中央高校基本科研项目(541109030099)。

摘　　要：为研究波形钢腹板梁焊接残余应力的分布规律,通过有限元软件建立其三维热弹塑性模型,利用热-力耦合分析技术对其焊接温度场和应力场进行有限元数值仿真,采用双椭球体热源和修改单元材料属性的方法实现能量输入和焊缝填充,并将模拟计算结果与实测值进行对比分析.结果表明:有限元预测的波形钢腹板梁残余应力分布与实测结果具有相同趋势,在波形钢腹板梁焊缝的弯折角处,残余应力发生一定幅度的连续应力波动;底板和腹板的残余应力峰值均出现在焊缝中心区域,其值分别为材料屈服强度的1.30倍和1.26倍;底板纵向残余拉应力在焊缝中心线两侧78 mm范围内急速下降后缓慢过渡为压应力,在底板较窄一侧压应力线性增大,最大值约为材料屈服强度的0.61倍;在底板较宽一侧压应力线性减小,并在边缘处转化为拉应力;焊接速度对残余应力分布扰动不大,而对残余应力峰值影响较显著;当焊接速度从150 mm/min增加至250 mm/min时,横向和纵向的残余应力最大值分别增加了27.11%和5.88%.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.

关 键 词：波形钢腹板梁 焊接残余应力 热力学 数值模拟 焊接速度 

分 类 号：U441.5[建筑科学—桥梁与隧道工程]