变截面门式刚架的几何非线性性能

Geometrically nonlinear performance of portal frame with tapered members

基于二维等截面梁元几何非线性有限元理论,按照更改的拉格朗日列式法,推导了等截面梁元弹性刚度矩阵与几何刚度矩阵,并推广到变截面梁元;通过对刚架几何非线性性能的分析,结果表明刚架刚度、刚架高度以及水平荷载对刚架几何非线性的影响较大。

Based on the theory of two dimensions nonlinear finite beam element with equal section, elastic stiffness matrix and geometric stiffness matrix was deduced according to Updated Lagrangian Formulation in this paper.Furthermore, the matrix was extended to finite beam element with tapered members, through the nonlinear performance analysis of portal frame. It showed that stiffness, height and horizontal load have great influence on portal frame.