Updating Modal In Matrix Form Basing On The Model Experimental Data

Building a high-quality finite element model of structural dynamics is the key solution in the analysis of structural dynamics. However, the errors which are inevitable between finite model and experimental model are significant on occasion due to the presence of various theoretical hypotheses, the approximate boundary conditions, uncertainty of material real parameter, inappropriate simulation of connection stiffness and support stiffness, ignorance or inaccuracy of damping characteristics and so forth. Thus, the updating model technique is available to modify the built finite element model of dynamics. The thesis researches the updating finite element model of matrix form based on the model experimental data, and puts forward a method of updating finite element model of matrix by repeatedly adding known masses or stiffness. The method increases the number of requisite identified equation effectively, solves the problem of model updating lower accuracy resulting from insufficient model tested number, and makes the model testing experiment utilized by model updating conveniently and flexibly. In this paper, by model updating on the base of repeatedly adding known masses and stiffness simultaneously of a flutter, it shows the simplification and accuracy of the proposed new matrix model updating compared with the previous model updating.