【提要】 采用ANSYS软件中【板壳】，考虑双重非线性，对梁端受等弯矩、不等同号弯矩、不等异号弯矩和梁上均布荷载和两端简支与固接情况下双段变截面H型钢梁进行了全过程分析，并同时考虑了纵向焊接残余应力、初始几何缺陷的影响。根据获得的构件荷载位移曲线和不同荷载时刻的构件整体与局部变形形态，对比分析了不同荷载工况对双段变截面梁的承载力、整体刚度、相关屈曲、塑性扩展等性能的影响。研究结果表明，对于受弯矩作用的双段变截面H型钢薄壁梁，其腹板宽厚比可尽量取大值；剪力对梁的相关屈曲性能影响很大，对主要受剪力作用的梁，要防止发生腹板局部屈曲；固接约束极大改善构件性能。
【关键词】 相关屈曲 双段【截面 H】钢薄壁梁 荷载工况 双重非线性
Interactive Buckling Analysis for Hsection Double Tapered Steel Beams Under Various Loading Style/Yang Na, Long Lihua, Yang Qingshan(School of Civil Engineering and Architecture, Beijing Jiaotong University, Beijing 100044,China)
Abstract:The interactive buckling performance of double tapered Hsection steel beams used in portal frame structures is analyzed by ANSYS, in which geometric and material nonlinearity are considered and shell element is adopted. According to the loaddeflection curves and deformation shapes of members obtained, interactive buckling, global stiffness and capability and plasticityspreading behaviors of Hsection tapered beams under different loading are discussed. Some valuable conclusions are drawn.
Keywords:buckling; double tapered Hsection; steel beams; thin web；loading style；geometric and material nonlinearity

*国家自然科学基金资助项目（50308001）。