大跨度架桥机钢桁架的稳定与极限荷载分析

Lateral Stability and Limit Load of Long-Span Steel Truss for a Girder Erection Machine

基于有限变形理论 ,考虑截面翘曲变形影响 ,推导了空间闭口薄壁箱型梁的UL列式增量平衡方程 ,建立了薄壁箱型梁的非线性稳定计算方法 ,并编制了相应的程序 .将架桥机的两个单梁换算为等效闭口箱型梁 。

In this paper a new formulation for the large_displacement elastic_plastic analysis of spatial steel frame is presented. Based on the virtual work equation of closed thin_walled beam accounted for warping deformation of the section, the proposed formulation is derived in UL formulation. And a program is developed to analyze the closed thin_walled section beam structure. By using the proposed approach, the spatial steel trusses for girder erection machine are converted into two thin_walled beams, and then the limit load and lateral buckling of steel truss is calculated.