DYNAMIC OPTIMIZATION DESIGN OF EXTRADOSED CABLE-STAYED BRIDGE UNDER EARTHQUAKE EXCITATION

An extradosed cable-stayed bridge, Dalian Changshan bridge, is used as an engineering background to study the dynamic optimization of the structure under earthquake excitations. The purpose of the research is to improve the static and dynamic characteristics of this bridge structure, to improve structural seismic performance, and to ensure it can work safely and reliably in dynamic environment. Firstly, the spatial finite element model of Changshan bridge is established in ANSYS. Then the response surface method is employed to optimize the bridge vibration frequency, and the optimum design of structural dynamic characteristics is carried out. In addition, the optimization method of experimental design is choosing to optimize the dynamic response of the structure under earthquake excitations, and the optimal design of structural dynamic response is carried out. Finally, the neural network is used to establish a network model to predict the structural seismic response quickly and effectively, which provides a reference for the optimum design of the bridge structure. The research results show that: the structural dynamic optimization design can fully exert the potential of the structure and reduce the seismic dynamic response of the bridge under the premise of ensuring the integrity of the bridge structure.