关键词: 动力修改, 模型缩聚, 有限元法

Abstract: For model updating purposes the dynamic or static condensation technique are often used to reduce the size of the analytical finite element model due to the size and mesh incompatibility of the experimental and FE models. It is recognized that the physical meaning of the updated model disappears due to model reduction. In this paper the transformation relation between the unmeasured and measured mode shapes is obtained by means of the modal matrix of the analytical FE model. The stiffness and mass matrices are condensed by the relation. Based on the reduced matrix eigen-equation, a method is proposed to locate the physical position of modelling errors in stiffness by using modal test data and the analytical stiffness and mass matrices. The effectiveness of the method is demonstrated through a numerical example.

Key words: model updating, model condensation, finite element method