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 gen-eration 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 in-side 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
Key words
steel-concrete composite bridge/large-diameter studs/sequential thermal coupling/weld-ing temperature field/welding residual stress
维普
万方数据