Analysis of Damage Mechanism of Heihe Bridge during the Maduo Earthquake

It is of great significance to discuss the earthquake damage mechanism of the bridge. In this paper, the seismic damage mechanism of Heihe Bridge is analyzed based on the post earthquake data. Firstly, the seismic response of Heihe Bridge is analyzed based on the finite element software Midas/Civil, and the model of Heihe Bridge (upward) is established using the data of Dawu strong earthquake records near the bridge site; Then, the influence of bridge connecting plates on the seismic response of small and medium span simply supported girder bridges is studied, and the models with and without connecting plates are established. Finally, through the experimental analysis of the ground motion response, the internal force relationship between the connecting plate and the substructure of the bridge is discussed. The results show that:1)Abutment plays an important role in restraining the displacement of main beam along the bridge. Bridge connecting plate is an important seismic measure. (2) Using the three-dimensional ground motion simulation method of random finite faults, the seismic response analysis of the given USGS ground motion can better simulate the failure mechanism of the bridge. (3)The seismic response of the structural system is determined by the different layout of the bridge deck.