超高强度钢材焊接箱形轴心受压柱整体稳定的有限元分析

Finite Element Analysis on Overall Buckling of Ultra-High Strength Steel Welded Box Section Columns under Axial Compression

目的运用有限元方法分析计算超高强度钢材焊接箱形截面轴心受压柱整体稳定受力特性的准确性和可靠性,以及残余应力的影响.方法运用通用有限元软件ANSYS建立三维有限元模型,准确模拟构件的残余应力和几何初始缺陷,对11个超高强度钢材焊接箱形截面轴心受压柱的整体稳定受力特性进行了有限元分析,并与相应的试验结果进行对比.结果有限元计算得到的承载力与试验实测结果的平均误差<4%,且标准差<5%.残余应力的2种变化对整体稳定承载力的影响<3%.结论建立的有限元模型能够准确地分析计算超高强度钢材轴心受压柱的整体稳定受力特性,为进一步运用该有限元模型对各种截面的超高强度钢材轴心受压柱的整体稳定受力特性进行分析计算提供了正确性依据.残余应力的变化对超高强度钢材焊接箱形截面轴心受压柱整体稳定承载力的影响较小,可能采用比普通钢材钢柱高的整体稳定系数.

Finite element models are developed by using the general-purpose finite element software, ANSYS, with accurate simulation of the residual stress and the initial geometric imperfections of the specimens, to analyze and calculate the overall buckling behaviour of 11 ultra-high strength steel welded box section columns under axial compression. By comparing the finite element analysis （FEA）results with the corresponding tests results, it has been verified that the finite element model created in this paper can accurately simulate and analyze the overall buckling behaviour of ultra-high strength steel welded box section columns under axial compression. So this finite element model is validated to do further finite element parametric analysis on the overall buckling behaviour of ultra-high strength steel columns under axial compression in order to determine the buckling curve and the buckling reduction coefficient. By applying different residual stress distributions in the finite element analysis and comparing the results, it can be concluded that the influence of the variation of the residual stress on the overall buckling resistance of the ultra-high strength steel columns is not so much.