中文摘要：

随着钢结构的发展，高强度热轧等边角钢在钢结构中的应用逐渐增多，如输电铁塔和大跨度桁架等。然而由于强度的提高，较多数量角钢截面的等效宽厚比超过规范的限值，不满足局部稳定的要求。我国现行规范尚未对这一问题给出明确规定。运用通用有限元软件ANSYS建立有限元模型，准确模拟构件的残余应力和几何初始缺陷，对15个高强度热轧等边角钢轴心受压构件的局部稳定受力性能进行有限元分析，并与相应的试验结果进行对比。比较结果表明，建立的有限元模型能够准确模拟几何初始缺陷和残余应力对构件局部稳定受力性能的影响，从而准确地分析计算高强度热轧等边角钢轴心受压构件的局部稳定受力性能。利用已验证的有限元模型，对高强度热轧等边角钢轴心受压构件的局部稳定受力性能进行有限元参数分析，并与美国规范和欧洲规范的设计方法进行对比。结果得到：几何初始缺陷和残余应力对于高强度热轧等边角钢轴心受压构件局部稳定承载力的影响比普通钢材受压构件小；美国钢结构设计规范能够更准确的计算Q420等边角钢轴心受压构件的局部稳定承载力。

英文摘要：

With the development of steel structures, the application of high strength hot-rolled steel equal angles in steel structures is increasing, especially in transmission towers and long span trusses. But because of the high strength, the width-to-thickness ratios of many steel angles exceed the code limitation, which does not satisfy the requirement of against local buckling. The Chinese codes do not provide specified regulation for the problem. Finite element models are developed using the general-purpose finite element software, ANSYS, for accurate simulation of the residual stresses and the initial geometric imperfections of the specimens to analyze the local buckling behavior of 15 high strength steel equal angle columns under axial compression. By comparing the finite element analysis （FEA） results with the corresponding test results, it is verified that the finite element model can accurately simulate the initial geometric imperfections and residual stresses of the columns, and analyze the local buckling behavior of high strength steel equal angle columns under axial compression. By using the verified finite element model, parametric analysis is conducted, and the results are compared with those from the design methods in American and European codes. It can be concluded that, the influences of the initial geometric imperfections and residual stresses on the local buckling capacity of high strength steel equal angle columns under axial compression are less than that of ordinary strength steel equal angle columns, and the American steel structures design code can calculate the local buckling capacity of Q420 steel equal angle columns under axial compression more accurately.