Finite Element Model Updating Research Of Single Pylon Cable-Stayed Bridges

Finite element model updating is the process of decreasing the gap between the measured value and the calculated value of the finite element model through the identifying and updating of design parameters, and establish the finite element model to reflect the actual state of the existing structure, essentially within the optimization problem.The finite element model updating has wide applications in the design and damage assessment of bridge health monitoring system, the bridge custody system design, thus, the finite element model updating study has good practical value.The main work includes:1. Review the course of development of the finite element model updating, and summarize the finite element model updating methods, to analyze the advantages and disadvantages and problems of each method;2. The introduction of combining sub-structure and radial basis function neural network method as finite element model updating tool of this thesis, the "inverse problem" transformed into "normal problem" is solved;3. Consider the characteristics of the finite element model updating problems, analyse the input and output parameters of radial basis function neural network, and determine the technology roadmap using the radial basis function neural network to update the finite element model;4. Update the prestressed concrete simply supported beam finite element model, and verify the feasibility of the proposed method;5. Using stochastic subspace method to analyze the measured dynamic data of the single pylon cable-stayed bridge, access to the structural natural frequencies and mode, it is used to update the single pylon cable-stayed bridge. The gap between the calculation results of updated finite element model and measured value is much more decrease than the original design finite element model.