考虑非线性扭转影响的薄壁梁翘曲特性分析

WARPING INVESTIGATION OF THIN WALLED BEAMS WITH NONLINEAR TORSION

考虑翘曲和大扭角变形的影响 ,研究薄壁梁结构轴向与扭转非线性耦合弹性变形问题。忽略高阶非线性的影响 ,结合升阶谱有限元方法 ,形成对称的非线性几何矩阵 ,从而建立一个稳定的非线性方程数值解模型。针对矩形截面薄壁梁结构 ,通过与线性结果对比 ,分析非线性对截面翘曲正应力。

A nonlinear mathematical model is developed to describe the nonlinear deformation of a thin-walled beam with the single closed cell under the influence of the nonlinear torsion. By using the hierarchical finite element method, the symmetrical geometry stiffness matrix is given. Then, a stable nonlinear numerical algorithm is formed. In the cast of a thin-walled rectangular beam, the nonlinear results are compared to the linear results to analyze the nonlinear effects on the main mechanical behaviors that include direct warping strain and the angle of torsional rotation of a cross section.