钢混组合桥梁大直径栓钉焊接残余应力研究  

Study on Welding Residual Stress of Large-diameter Stud of Steel-concrete Composite Bridge

作　　者：朱豪杰 张谢东[1] 李朝惠 李勇 林源 吴迪 ZHU Haojie;ZHANG Xiedong;LI Chaohui;LI Yong;LIN Yuan;WU Di(School of Transportation and Logistics Engineering,Wuhan University of Technology,Wuhan 430063,China;Hubei QiaoXiao Expressway Management Co.Ltd.,Wuhan 430000,China)

机构地区：[1]武汉理工大学交通与物流工程学院,武汉430063 [2]湖北硚孝高速公路管理有限公司,武汉430000

出　　处：《武汉理工大学学报（交通科学与工程版）》2024年第6期1211-1217,共7页Journal of Wuhan University of Technology（Transportation Science & Engineering）

摘　　要：文中以某钢混组合梁桥为背景,依据该桥大直径栓钉焊接施工方式与焊接工艺参数,建立大直径栓钉焊接顺序热力耦合有限元模型,研究大直径栓钉焊接温度场与残余应力场的大小及其分布规律,探讨大直径栓钉焊接残余应力的产生机理.结果表明:大直径栓钉焊接加热过程中,高度集中的热流持续输入,焊接熔池周围等温面呈椭球面分布,熔池内部材料屈服,熔池边缘Mises等效应力峰值达到304.7 MPa,在焊接区域产生径向压缩残余应力.大直径栓钉焊接冷却过程中,由于热对流与热损失,熔池从液相重新转变为固相,栓钉与母材逐渐冷却至环境温度,焊接区域Mises等效应力逐渐增大至常温下材料的屈服强度值358 MPa,在焊接区域产生径向拉伸残余应力.Taking a steel-concrete composite beam bridge as the background,according to the welding construction mode and welding process parameters of the bridge,a thermo-mechanical coupling finite element model of welding sequence of large diameter studs was established.The size and distribution of welding temperature field and residual stress field of large diameter stud were studied,and the generation mechanism of welding residual stress of large diameter stud was discussed.The results show that during the welding and heating process of large-diameter stud,highly concentrated heat flux is continuously input,and the isothermal surface around the welding pool is ellipsoid.The material inside the molten pool yielded,and the peak value of Mises equivalent stress at the edge of the molten pool reached 304.7 MPa,resulting in radial compressive residual stress in the welding area.During the cooling process of large-diameter stud welding,the molten pool changed from liquid phase to solid phase again due to thermal convection and heat loss.The stud and the base metal gradually cooled to ambient temperature,and the Mises equivalent stress in the welding area gradually increased to the yield strength of the material at room temperature of 358 MPa,resulting in radial tensile residual stress in the welding area.

关 键 词：钢混组合桥梁 大直径栓钉 顺序热力耦合 焊接温度场 焊接残余应力 

分 类 号：U443[建筑科学—桥梁与隧道工程]