悬索结构非线性有限元分析

提出了一种适合于悬索结构空间非线性分析的三节点等参数索单元有限元模型，在三维整体坐标下，由就的定义得到了可以考虑任意高阶位移影响的非线性应变几何关系，采用Ｌａｇｒａｎｇｉａｎ坐标描述法，并由虚功原理建立了非线性有限无限元增量方程及切线刚度和矩阵，算例计算表明，本文方法可用于各种悬索结构的计算分析。

A Nonlinear Finite Element Method for Analyzing Cable Structures

This paper presents a nonlinear finite element method with three node isoparametric cable element for the analysis of cable structures.Under the Lagrangian coordinate of three dimensions,by means of the definition of the Lagrangian strain,the nonlinear geometrical expression of the precise strain is set up,with which the effect of displacement with the terms of any high orders can be considered.By use of the virtual displacement principle,the incremental finite element equation is derived and the tangent stiffness matrix is obtained.The results of a computation example show that the present method is of high precision,and can be applied in the analysis of cable structures.