单层网壳结构随机缺陷模态法研究

随机缺陷模态法是分析网壳结构缺陷的常用方法,传统的方法以节点位移为随机变量进行缺陷结构的稳定性分析,为了使理论上更加合理及能够考虑初应力的影响,本文选取结构的基本参数(杆件长度、钢管外径、弹性模量、钢管厚度)为基本的随机变量。根据这种思想,通过数值计算发现了杆件长度对结构稳定承载力的影响最为显著,拟合了网壳结构极限承载力的概率分布,确定了规范规定的可靠度指标下的临界荷载标准值。

Study of stochastic imperfection method for stability analysis of single layer lattice shell

Stochastic imperfection method is a common method to analyse lattice domes.Custom stochastic imperfection method assumes node displacement as a stochastic variable to study a lattice shell,however,in order to build a appropriate model and to take account initial stress,we take basic parameters such as length,diameter,width and module of member bar as basic stochastic argument.According to this idea,we analysed the influence to shell stability by the parameters above,confirmed the distribution of shell limited load and determined the normal value of the bearing capacity under a certain reliability index.