Finite Element Model Modification of an Arch Bridge Based on Response Surface Method

Usually the structure of the initial finite element model can not reflect the actual situation of structure, the finite element model updating is for the initial finite element model of the structure, according to the static and dynamic response of the structure of the measured optimize the model parameters are adjusted, the revised model response is more close to the actual structural response, so as to get a more accurate finite element model. In this paper, the finite element model of the bridge is updated by using the second order incomplete polynomial response surface model. Then determine the sample data, use the least squares method to fit the undetermined coefficients of the second-order incomplete polynomial, and perform the accuracy test. Then the objective function based on frequency is constructed, and the updated optimal design parameters are obtained by quadratic sequence programming. Finally, using the optimal design parameters for modal analysis, it is found that the frequency error has decreased. It is proved that the correction by the response surface method (RSM) can improve the accuracy of the finite element model.