基于有理逼近和灵敏度分析的结构动力重分析方法

NOVEL METHOD FOR STRUCTURAL DYNAMIC REANALYSIS BASED ON RATIONAL APPROXIMATION AND EIGEN-SENSITIVITY

提出了一种新的结合特征灵敏度直接法和向量值函数有理逼近的结构动力重分析方法。给出了直接法简单特征对n阶灵敏度分析的一般表达式。利用向量值函数有理逼近,减小固有振型n阶Taylor展开的截断误差。数值算例表明,对结构设计参数作大修改时,该方法能够给出高精度的逼近结果。新方法不需要系统的全部模态,因此,适用于大型复杂结构的动力重分析。

A new method of rational approximation for structural reanalysis based on perturbation method is proposed in this paper.The new method is based on combining perturbation method of eigen-problems with rational approximation of a vector-value function.The generalized expressions of the nth order derivatives of distinct eigen-solutions are also proposed in this paper.The new method reduces the error of truncated Taylor Expansion.The numerical example illustrates that the proposed method can provide high quality approximations of the structural behavior for large changes in the design parameters.The proposed method is also available for large complex structures due to its no use of the whole modal information.