基于改进的基本效应法的网壳结构构件重要性分析方法

Member Importance Analysis Method of Spatial Latticed Shell Structures Based on Improved Elementary Effects Method

摘要:

现有的网壳结构构件重要性计算方法仅考虑单根构件损伤或失效对结构的影响，未考虑构件间的相互作用和损伤的随机性。为解决这一问题，首先将基本效应法应用于构件的重要性判定中，定义了适用于网壳结构的基本效应；其次，将构件分为重要构件和一般构件两类，提出试算与正式计算结合的双阶段判定方法，以提高确定重要构件的计算效率；提出基于优劣解距离法的重要性排序方法，以确定重要构件内部的相对重要性排序；由此，进一步提出了基于改进的基本效应法的网壳结构构件重要性分析方法。此外，为减小改进的基本效应法的计算量，提出适用于该方法的修正径向抽样方法。凯威特型球面网壳数值算例分析结果表明：与现有方法相比，采用该方法确定的重要构件进行抽样检测鉴定时，评定网壳极限承载力的估计误差显著降低。

Abstract:

The existing member importance calculation methods of spatial latticed shell structures only analyze the influence of the damage or failure of a single member on the total structure， without considering the random damage and interaction of members. To solve these problems， this paper introduces the elementary effects method into member importance analysis for the first time， and the new elementary effect is defined for spatial latticed shell structures. Meanwhile， members are divided into importance members and general members， and the two-stage decision method combining trail calculation and formal calculation is proposed to improve the calculation efficiency of determining importance members. Besides， the importance ranking method based on the technique for order preference by similarity to an ideal solution （TOPSIS decision method） is proposed to determine the relative importance ranking of important members. In summary， the member importance analysis method based on the improved elementary effects method is proposed. To reduce the calculation budget of the improved elementary effects method， a modified radial sampling strategy is proposed. The analysis results of the Kiewitt shell numerical model shows that compared with existing methods， random sampling based on the important members determined by the proposed method can effectively reduce the estimation error of the ultimate bearing capacity of the shell structure.