Study On The Seismic Resistance Peformance Of Vertical Prestressed Self-centering Isolation Pier

Self-Centering isolation pier is separated at parting plane between bottom of pier and foundation, in a rare earthquake, the pier can consume part of seismic energy through swing and protect the bridge pier and foundation. After the earthquake, the pier can be reset relying on its own gravity. Pre-stressed technology in the application of ordinary bridge pier is common, but few studies in self-centering isolation pier. By adopting the numerical method, seismic resistance performance of self-centering isolation pier with vertical distribution of pre-stressed steel is studied. The main research contents and results are as follows:(1) Based on consulting literature, the development and application of self-centering isolation pier and research status both at home and abroad are summarized.(2) Introduces the basic principle of isolation and isolation structure seismic response analysis method.(3) Introduces several model of self-centering isolation pier, based on the model of two-spring model, the model of self-centering isolation pier with vertical distribution of pre-stressed steel is carried out.(4) Based on a newly built railway bridge, single pier analysis model is established, using the nonlinear time history analysis method, studies the two-spring model and vertical pre-stressed self-centering isolation pier model and compared the results of seismic response. The results show that the seismic resistance performance of self-centering isolation pier is improved significantly after prestress is act on the original structure.(5) The influence factors of prestress on seismic isolation performance of bridge pier is studied. Parameters of the comparative analysis is done through change those influence factors. The results show that the value of prestess has a large influence on the pier seismic response, appropriate value of prestress can improve the seismic resistance performance of self-centering isolation pier; the position of prestress has the large influence on its maximum horizon displacement.