An Improved Method of Bridge Finite Element Model Update by Stepwise Regression
With the increasing of variables and orders of polynomial expansion, the undetermined coefficients of the response surface model have increased dramatically. The insignificant expansion terms should be eliminated because not all of the expansion terms have significant effect on the response. The improved and practical updating method based on response surface model by stepwise regression, which can effectively reduce the undetermined coefficients on the premise of guaranteeing the correcting accuracy, is proposed in this paper. The method is also applied to update the finite element model of a bridge with prestressed reinforced concrete rigid frame-continuous girders based on the in-situ dynamic test results. The results show that the updated finite element model can match the mechanical properties of the bridge well.