基于试验模态参数的有限元模型的结构参数辨识

Identification of Structural Parameters of Finite Element Model Based on Testing Modal Parameters

以结构系统的正交特征方程等为约束条件，从求解带约束的拉格朗日函数极值入手，提出了一种用测试的非完全模态参数辨识结构参数的方法，通过算例说明了该方法在模型中有不易测得的自由度或为聚缩模型时的应用。本文方法可用于复杂有限元模型中的参数辨识。算例表明：本文方法有较大的误差修正范围。

Taking the orthogonality and the eigenvalue eguation of the structural system as the constraint conditions and beginning by solving the limit value of Lagrange function with constraints,this paper proposes a method for identifying the structural parameters by using the measured incomplete modal parameters. Through given examples, it illustrates that the method involves the hardly measured degree of freedom in model or gets application in the reduced model. The given method may be applied to identify parameters in complex finite element model. The results of examples have shown that the relatively large deviations between analytic natural frequencies and measured ones can be improved by the method and it is effective and has a good accuracy.