Analysis Of Finite Element Model Updating Based On Viscous Damping System

In recent decades, in order to improve the accuracy of finite element simulation, model updatingtechnique has been widespread concern in the field of science and technology and industrialapplications and has been developing rapidly. On the basis of cross-model cross-mode method, thepaper proposes three model updating methods. Through the model updating process of proportionaldamping model and viscous damping model, discuss the advantages and disadvantages of the threemethods and select the best model updating method. This paper studies the impact of the parameterselection. And the method used to update the actual structure of the project. Details are as follows:This paper describes several classical methods of the finite element model updating, and discussthe advantages and disadvantages of various updating methods. This paper proposes the basic selectprinciples of the model updating. For problems with viscous damping and numerical singularity, thispaper put forward three updating methods. They are damp-cross-model cross-mode method(DCMCM), Improve damp-cross-model cross-mode method (DICMCM) and Improvedamp-cross-model cross-mode anti multiply method (DICMCM AM). By numerical example,Improve damp-cross-model cross-mode method can solve these problems and get higher accuracyresults.This paper studies the impact of the parameter selection. In selecting a different modal situation,this paper verifies the accuracy of the results of DICMCM. Selecting different number ofexperimental modal greatly impact the result of the updating. Therefore, in the updating process weshould select a large number of experimental data in order to obtain a more accurate updating result.Iterative updating weakly impact the result of the updating. This method does not require iterative andsave computing time.In this paper, we update a steel structure with the new model updating method, and verifywhether it meets the requirements of structural dynamics engineering analysis. The results showedthat: Updated model results fit the experimental results. The frequency error of the updated model isbelow3%. Therefore, the proposed method has practical value in engineering.