Q460高强钢焊接箱形柱轴心受压极限承载力参数分析  

Parametric analysis of ultimate bearing capacity of Q460 high strength steel welded box columns under axial compression

作　　者：李国强[1] 王彦博[2] 陈素文[1] 孙飞飞[1] 

机构地区：[1]同济大学土木工程防灾国家重点实验室,上海200092 [2]同济大学土木工程学院,上海200092

出　　处：《建筑结构学报》2011年第11期149-155,共7页Journal of Building Structures

基　　金：国家自然科学基金项目(90815029)

摘　　要：为研究现有钢结构设计规范是否仍适用于高强钢中厚板焊接箱形柱的设计,对Q460钢轴心受压柱的极限承载力进行了参数分析。采用数值积分法,并与有限元程序ANSYS的数值计算结果作进行对比。数值模型考虑了1/1 000柱长的初始弯曲及由相应截面尺寸残余应力试验提出的残余应力分布简化模型。试件的主要参数为截面宽厚比(7.8～17.2)与柱长细比(10～130)。计算结果表明:考虑相同初始缺陷的有限单元法与数值积分法所得计算结果吻合较好;与普通强度钢柱相比,初始几何缺陷对高强钢焊接箱形柱的极限承载力影响降低,柱的稳定系数提高;残余应力降低柱的稳定系数,但其影响效应随长细比变化。参数分析结果与现有规范计算结果对比表明,中厚板Q460高强钢焊接箱形柱,当宽厚比b/t≤20时,可采用高于普通强度钢柱的b类柱子曲线。A parametric analysis on ultimate bearing capacity of fabricated box-section steel columns with the nominal yield strength of 460 MPa was presented.The analysis aims to investigate whether the current design codes for ordinary steel are applicable for high strength steel columns or whether the codes need to be modified to include high strength steel.The calculation program base on numerical integration method（NIM） was written by authors.And the commercial finite element analysis software ANSYS was also adopted for comparison.Numerical models including initial geometric imperfections and residual stresses were verified by test results.The main parameters were width to thickness ratio and column slenderness,which ranged from 7.8 to 17.2 and from 10 to 130 respectively.The effects of residual stresses and initial geometric imperfections on the ultimate bearing capacity with varyious parameters were investigated and discussed.A proposal for the design of high strength steel columns was given based on the comparison of parametric analysis with GB 50017—2003.The curve b,which is higher than the suggested curve c for ordinary steel welded box columns,suits better for the design of box columns fabricated from Q460 steel plates with width to thickness ratio no more than 20.

关 键 词：高强钢 焊接箱形柱 轴心受压 极限承载力 参数分析 

分 类 号：TU391.02[建筑科学—结构工程]