结构有限元模型的试验建模

 对于复杂结构系统,用试验测取的模态参数来识别或修改系统的物理参数,以构造其动态数学模型。这种方法是建立振动系统数学模型的逆方法。 近些年来,国内外不少学者在这一领域做了很多工作。他们方法的共同点是识别系统的总质量矩阵和总刚度矩阵,因此未知量较多。考虑到结构系统总矩阵元素之间有一定关系,文献3]讨论了一种建立动态有限元模型的逆方法。

STRUCTURAL FINITE ELEMENT MODELING BY TESTING METHOD

A method of dynamic finite element modeling of structure system using measured modal parameters (natural frequencies and mode shapes) of lower orders is presented in this paper. The finite element model is expressed by element mass and stiffness parameters, which are determined by minimization of weighted Euclidean norms of orthogonality conditions and characteristic equations. Using this method, the problem is reduced to solving linear algebraic equations. The number of structural parameters to be identified isn't many and the calculation is simpler. A sample problem is given to demonstrate the validity of the proposed method.