焊接初始缺陷对腹板开孔梁极限承载力的影响研究

Influenceof Initial Welding Imperfections on the Ultimate Bearing Capacity of Plate Girderswith Perforated Web

船体结构中的腹板开孔梁在加工和装配过程中会产生一定形式的初始缺陷,包括初始变形和焊接残余应力.采用非线性有限元软件ABAQUS分析了初始变形、焊接残余应力以及两者综合作用对腹板开孔梁结构极限承载力的影响.计算结果表明:初始变形的存在会显著降低构件的极限承载力,板型缺陷的影响约为9%,侧移型缺陷的影响约为5%,柱型缺陷的影响约为1%.焊接残余应力对开孔梁构件极限承载力的影响很小,最大影响为2.64%.初始变形和焊接残余应力同时存在时,开孔梁极限承载力的降低幅度小于初始变形和焊接残余应力单独影响之和.

Some initial imperfections,including initial deformation and welding residual stress,will occur in the process of processing and assembling the web perforated beam in the hull structure.The nonlinear finite element software ABAQUS was used to analyze the effects of initial deformation,welding residual stress and their combined effects on the ultimate bearing capacity of web perforated beam structures.The calculation results show that the existence of initial deformation will significantly reduce the ultimate bearing capacity of the component.The influence of plate type defects is about 9%,the lateral displacement defects is about 5%,and that of column type defects is about 1%.The welding residual stress has little effect on the ultimate bearing capacity of the web perforated beam,with the maximum effect being 2.64%.When the initial deformation and the welding residual stress exist simultaneously,the reduction of the ultimate bearing capacity of the web perforated beam is smaller than the sum of the initial deformation and the welding residual stress.