绝对位移直接求解的虚拟激励法  

Pseudo excitation method based on solving absolute displacement

作　　者：李永华[1,2] 李思明[2] 

机构地区：[1]南昌大学建筑工程学院,南昌330029 [2]同济大学土木工程学院,上海200092

出　　处：《振动与冲击》2009年第10期185-190,共6页Journal of Vibration and Shock

基　　金：国家自然科学基金创新研究群体项目(50621062)

摘　　要：在多点激励动力分析中,传统的虚拟激励法将绝对位移分解成拟静力位移和动态相对位移两部分,而且在构造虚拟加速度及位移激励进行求解时须计算结构拟静模态矩阵,所以必须编制专用程序用于求解,这在一定程度上限制了虚拟激励法的应用。提出了一种绝对位移直接求解的虚拟激励方法,该方法通过在支座附加一大质量块并对大质量块构造虚拟力激励从而实现对绝对位移直接求解。该方法不需要另外计算拟静模态矩阵,所以新虚拟激励法可应用于任何具有简谐振动分析模块的有限元软件如ANSYS等,这为虚拟激励法工程应用开拓了广泛的前景。In conventional pseudo excitation method(PEM),the free nodal absolute displacements are decomposed into pseudo-static and dynamic parts,respectively,in multi-excitation analysis.The pseudo-static displacement response matrix due to a unit displacement at restrained supports must be obtained for constructing a pseudo acceleration and displacement harmonic excitation,so a special program must be developed for conventional PEM,therefore it is inconvenient to use PEM widely in engineering to some extent.A new PEM was presented here,with it the free nodal absolute displacements could be solved directly by adding a big mass in support nodes and constructing harmonic pseudo force excitation to the big mass,so it was not necessary to calculate pseudo-static displacement matrix.New PEM could be used directly in any finite element software where harmonic response analysis could be performed,such as,ANSYS,etc.New PEM was more convenient to use in engineering than the conventional PEM.

关 键 词：虚拟激励 多点激励 绝对位移 ANSYS 

分 类 号：TU311.3[建筑科学—结构工程]