关键词: 有限元模型修正, 径向基神经网络, 单塔斜拉桥, 子结构, 相对灵敏度

Abstract: In order to obtain the contemporary state for the cable replacement project of one certain existing single pylon cable-stayed bridge with double cable plane，a new combined method for finite element model updating is proposed． In the light of the parameterized model updating theory，the relative sensitivities of the calculated design parameters are analyzed to determine the will be modified parameters． Substructure method is introduced in the model updating process for meet the requirement of the parameter’s discreteness，and the calculated parameters in each substructure is regard as invariables． The radial basis function neural network ( ＲBF) is adopted as the optimization algorithm of model updating． Combination the substructure method and ＲBF，the intrinsic“inverse problem”of finite element model updating is transformed as the“forward problem”． The substructure partition，ＲBF neural network construction and its input and output parameters determination are discussed as well． A certain existing single pylon cable-stayed bridge is taken as the case study to verify the proposed combined model updating algorithm． The result shows that the discrepancy between the calculated value and measured valued decrease dramatically before and after the finite element model updating．

Key words: finite element model updating, radial basis function neural network, single pylon cable-stayed bridge, substruc-ture, relative sensitivity