Q420高强度等边角钢轴压构件整体稳定性能设计方法研究

为研究Q420高强度等边角钢轴压构件的整体稳定受力性能与设计方法, 该文采用有限元软件ANSYS建立数值模型, 并经与试验结果对比验证后进行了大量参数分析, 研究了构件几何初始缺陷、残余应力和钢材屈强比对该类轴压构件整体稳定性能的影响, 分析了已有设计方法的适用性。结果表明, 构件初始缺陷对其稳定性能的影响与构件长细比及失稳模态有关, 残余应力的影响与构件长细比有关, 钢材屈强比的影响较小。基于数值计算结果建议了Q420高强度等边角钢轴压构件考虑板件局部屈曲相关作用的整体稳定设计方法, 为补充和完善我国钢结构设计规范提供了参考, 同时也有利于促进高强度钢材在我国钢结构工程中的应用。

INVESTIGATION ON DESIGN METHOD OF OVERALL BUCKLING BEHAVIOUR FOR Q420 HIGH STRENGTH STEEL EQUAL-LEG ANGLE MEMBERS UNDER AXIAL COMPRESSION

In order to investigate the overall buckling behaviour and design method of Q420 high strength steel (HSS) angle columns under axial compression, a finite element model is developed through the finite element software ANSYS, which is validated against the test results and is utilized to undertake a large amount of parametric studies. The effects of the imperfections and Y/T ratio of steel on the overall buckling behaviour are elucidated, and the applicability of current design methods is analyzed. It is found that the effect of geometric imperfections is significantly related to the column slenderness and failure mode, and the effect of residual stresses is related to the column slenderness, whilst that of Y/T ratio is very slight. Design approaches for the overall buckling design method allowing for the local buckling are suggested for Q420 HSS angle columns, which contributes to the improvement of current steel structural design code, and has a potential application of HSS structures.