压弯构件的弹塑性分析

Derivation of elastic-plastic element stiffness matrix of compress-bending member

在很多弹塑性问题分析中需要随应力状态的变化,不断调整单元刚度矩阵中的有关元素。对于压弯构件,当截面出现塑性时,弹性时期的单元刚度矩阵已经不再适用,即轴力弯距出现耦合现象,需要重新计算本阶段的单元刚度矩阵。可基于截面刚度矩阵以及现有的位移模式推导出弹塑性阶段的单元刚度矩阵。

In many nonlinear fmite element analysis, so related element of the element stiffness matrix should be adjusted according to the variation of the state of stress. To compress - bending member, while plastic deformation occurred in the section, the element stiffness matrix of elastic was no longer valid, the element stiffness matrix of this stage should be recounted. According to section stiffness matrix and available displacement mode, element stiffness matrix of elastoplastic stage was derived in this paper.