非对称开口截面薄壁圆形曲梁的非线性自由振动分析  

Nonlinear Free Vibration Analysis of Asymmetric Thin-Walled Circularly Curved Beams with Open Cross Section

作　　者：Haijuan Duan 

出　　处：《钢结构》2009年第2期78-79,共2页Steel Construction

摘　　要：为具有非对称开口截面的薄壁曲梁的非线性自由振动分析构建了一个有限元公式,由虚功原理推导出动能和势能,并考虑了弯曲-扭转耦合、扭曲和剪心位置等影响。有限元分析中,2结点薄壁曲线构件的形状函数采用三次多项式计算。每个结点具有7个自由度,其中包括扭曲自由度。采用直接迭代法计算非线性特征值。将计算结果与直线梁的计算结果相对比。同时归纳了具有多种半径和对角的曲梁的非线性自由振动分析结果。A finite element formulation is present for the non- linear free vibration of thin-walled curved beams with non- symmetric open across section. The kinetic and potential energies are derived by the virtual principle. The energy functional includes the effect of flexural-torsional coupling, the torsion warping and the shear center location. For finite element analysis, cubic polynomials are utilized as the shape functions of the two nodal thin-walled curved elements. Each node possesses seven degrees freedom including the warping degree of freedom. The nonlinear eigenvalue problem has been solved by the direct iteration technique. The results are compared with those for straight beams as available in the literature. The results for nonlinear free vibration analysis of curved beams for various radii and subtended angle are presented.

关 键 词：非线性振动 薄壁曲梁 有限元方法 

分 类 号：TU33[建筑科学—结构工程]