The Seismic Response Analysis And Seismic Performance Evaluation Of Continuous Girder Bridge With Deepwater Elevated Pile Caps

With the rapid economic development of our country, bridge construction developed not only large span but also a lot of deep water bridge. Due to the deep water bridge faced deep river water and weak sedimentary rocks, pile foundation is able to penetrate the soil and reach the deeper bearing layer,at the same time with large rigidity, small deformation, riding smooth and comfort and other advantages of continuous girder bridge, so continuous girder bridge with deepwater elevated pile caps is widely applied to the construction of deep water bridge. Because of the complexity of seismic response and post-earthquake difficult repairment of continuous girder bridge with deepwater elevated pile caps,so the study is very necessary.This paper takes a continuous girder bridge with deepwater elevated pile caps as the engineering background, which was done seismic response analysis and seismic performance evaluation by considering the effect of hydrodynamic pressure.The main research work is as follows:(1)Through reading domestic and foreign literature of the interaction between structure and water, the earthquake damage of deep water bridges is introduced and the dynamic water pressure of bridge structure is considered as additional quality by using the Morison equation.(2) The modal analysis of continuous girder bridge with deepwater elevated pile caps is carried out to discuss the influence of hydrodynamic pressure on dynamic characteristics of continuous girder bridge with deepwater elevated pile caps, and the first to seventh natural frequencies and vibration modes are presented by considering dynamic water pressure.(3)Under the E1 earthquake, the continuous girder bridge with deepwater elevated pile caps was carried on response spectrum analysis and the effect of hydrodynamic pressure on pier bending moment without water and pier as well as piles foundation bending moment in water was discussed and the seismic performance evaluation of non water pier and water pier as well as water piles foundation was checked.(4)Under the E2 earthquake, the continuous girder bridge with deepwater elevated pile caps was carried on the elastic-plastic time history analysis and the seismic performance evaluation of non water pier and water pier as well as water piles foundation was checked.(5)The continuous girder bridge with deepwater elevated pile caps was carried on seismic isolation design by using friction pendulum isolation bearing,through parameter analysis of the friction pendulum isolation bearing,influence of isolation bearing sliding surface radius and friction coefficient on the pier bottom peak moment and the displacement of support are studied.The damping effect of friction pendulum isolation bearings is studied,and the seismic performance evaluation of non water pier and water pier as well as water piles foundation was checked.