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局部屈曲是钢结构构件的一种破坏模式,钢结构发生局部屈曲破坏时,屈曲应力小于钢材的屈服强度.为了研究高温下高强Q690钢柱的局部稳定性能,采用有限元软件ABAQUS建立有限元模型,模型采用其他学者完成的Q460钢柱轴心受压局部屈曲试验进行验证,考虑宽厚比、温度、初始缺陷、残余应力和翼缘与腹板之间相互作用的影响,对高强Q690钢柱进行参数分析.研究结果表明:宽厚比对局部屈曲有显著影响,宽厚比的增大导致试件极限承载力的降低;初始缺陷和残余应力对局部屈曲应力有较大影响,且试件的极限承载力随着温度的升高而明显下降.基于有限元分析结果提出了适用于高强Q690钢柱高温下的局部稳定设计方法和宽厚比限值,并与GB50017-2017、Eurocode 3和ANSI/AISC 360-10中的设计方法进行了比较.“,”Local buckling refers to a failure pattern of a structural steel member.It is characterized by lower ability to withstand compressive stress than the stress that the steel material is designed to withstand.This paper highlights the effects of local buckling on the structural behavior of steel columns subj ected to elevated temperatures with the aim of developing a suitable design method for the local buckling of the high-strength Q690 steel column at elevated temperatures.The local buckling of high-strength Q690 steel columns is numerically investigated by FE modeling using software ABAQUS.The developed FE models are validated against the experimental results of local buckling for high-strength Q460 steel columns under axial compression previously conducted by other researchers.Subsequently,a parametric study was carried out to evaluate the influence of several parameters affecting the design of steel members to resist local buckling such as the width-to-thickness ratio, temperature, initial imperfection, residual stress and interaction between the flange and web of the H-shaped cross-section.The results showed that local buckling is significantly affected by the width-to-thickness ratio;increasing the width-to-thickness ratio led to a reduction in the ultimate bearing capacity of the specimens. It also indicated that both initial imperfections and residual stress have a significant effect on local buckling stress.Furthermore,it was observed that the overall capacity of the specimens deteriorates significantly as the temperature increases. Based on the results,a simplified design method and new width-to-thickness ratio limits were proposed for the H-shaped high-strength Q690 steel compression members.The results data were also compared with the design rules provided by GB 50017-2017,Eurocode 3,and ANSI/AISC 360-10.