单层肋环型椭圆穹顶网壳整体稳定性分析

大跨网壳结构具有高度的几何非线性,结构设计一般由整体稳定性控制.本文以北京某单层肋环型椭圆穹顶网壳工程为背景,利用非线性有限元计算方法,对其整体稳定性进行了线性特征值屈曲、弹性屈曲以及弹塑性屈曲三方面的分析,并求得了它们的极限荷载.同时,还考察了钢材的屈服强度以及初始缺陷对极限荷载的影响,并将数值计算结果与拟壳法所得的设计临界荷载进行了比较,得出的结论对实际工程具有一定参考价值.

Study on global stability of the single-layer elliptical lattice dome

The structural design of large-span latticed shell is controlled by global stability due to the geometric nonlinear property.This paper presents the global stability analysis on a lattice dome.Linear eigenvalue bucking,elastic buckling and elastoplastic buckling on the single-layer elliptical lattice dome are carried out by the computational method of nonlinear finite element. Meanwhile,the influence of the yielding strength of steel and the initial imperfection on the ultimate load is investigated,the numerical results are compared with the design critical load obtained by quasi-shell method and some essential conclusions are drawn to assist the design of single-layer elliptical shell.