钢结构对接焊缝数值模拟及参数分析

Numerical simulation and parameter analysis of butt weld of steel structure

基于ANSYS有限元软件采用了双椭球热源模型、CO_(2)气体保护焊的焊接工艺,通过生死单元法模拟热源移动,建立了桥梁钢结构的焊接有限元模型,进行了对接焊缝的数值模拟分析,并与实验结果进行对比验证了模拟的可靠性。在此基础上研究了对接焊缝在坡口形状、X型坡口多层焊的焊接顺序、焊接速度、焊件厚度、焊接坡口角度、焊枪的施焊方向等不同因素下残余应力的变化情况。结果表明:相比于其他坡口的焊接,X型坡口焊接残余应力较小,多层焊情况时,X型坡口采用对称焊更有利;板厚、焊速的增加,坡口角度的减少及采用分中对称焊方法都能减少焊接残余应力的产生。

Based on ANSYS finite element software, the double ellipsoid heat source model, welding process for carbon dioxide gas shielded welding and the birth and death element method were used to establish the welding finite element model of the steel structure of the bridge, and the numerical simulation analysis of the butt weld was carried out, the simulation results were compared with the experimental results to verify the reliability of the simulation.On this basis, the variation of residual stress of butt weld under different factors such as groove shape, welding sequence of X-groove multi-layer welding, welding speed, thickness of welding piece, angle of welding groove and welding direction of welding torch were studied.The results showed that compared with other groove welding, X-groove welding residual stress was smaller, when multi-layer welding was used, symmetry welding was more favorable for X-groove welding, and the thickness of plate and welding speed increase, the reduction of groove angle and the adoption of symmetrical welding method can reduce the generation of welding residual stress.