中文摘要：

采用ANSYS软件建立焊接H形截面纯弯钢构件有限元分析模型,模拟截面残余应力、板件初始缺陷和几何非线性,分析强翼缘弱腹板和弱翼缘强腹板两组构件的弹塑性局部相关屈曲性能,分别讨论腹板高厚比、翼缘宽厚比和相对宽厚比（腹板高厚比与翼缘宽厚比之比）对构件局部稳定系数的影响。研究结果表明,局部稳定系数随腹板高厚比或翼缘宽厚比增大而显著降低,与相对宽厚比基本成线性关系;两组局部稳定系数拟合公式相对误差为-1.19%~1.15%,精度较高;可以根据整体稳定性和局部相关稳定性近似相等的原则,确定腹板高厚比和翼缘宽厚比限值相关曲线;平面外整体长细比较小时,钢结构设计规范的腹板高厚比和翼缘宽厚比限值部分超越宽厚比限值相关曲线。

英文摘要：

The finite element analysis model of a welded H-section steel member under pure bending moment was created with ANSYS to simulate the elasto-plastic local interactive bucking properties of two groups of steel members（ the strong flange and weak web group,and the weak flange and strong web group）,considering the sectional residual stresses,the plate initial imperfections and the geometrical nonlinearities.The influences of the web height-thickness ratio,the flange width-thickness ratio,the relative width-thickness ratio（ the ratio of web height-thickness ratio to flange width-thickness ratio） on the local interactive bucking coefficient were investigated,respectively.Study results show that the local interactive bucking coefficient decreases significantly as the web height-thickness ratio or the flange width-thickness ratio increases,and varies quasi-linearly with the relative width-thickness ratio.Two fitting formulas of local interactive bucking coefficient were achieved with high accuracy,and their relative errors were within-1.19% ~ 1.15%.According to the principle of simultaneous overall buckling and local interactive buckling,the web height-thickness ratio limit and flange width-thickness ratio limit correlation curves were derived,which might be partly surpassed by the web and flange width-thickness ratio limitations given in the Code for design of steel structures if the out-of-plane overall slenderness was relatively small.