Seismic Response Analysis Of (60+2×100+60)m Prestressed Concrete Continuous Beam Bridge

Prestressed concrete continuous beam bridges are widely used in the construction of high-speed railways because of their excellent durability,practicability,and safety,as well as low maintenance costs.Because of the high quality of prestressed concrete bridges,they are subject to enormous forces during earthquakes and are prone to structural damage,and China is a country with frequent earthquakes.Therefore,it is necessary to study and analyze the seismic response of prestressed concrete bridges.This paper simulated a(60+2×100+60)m prestressed concrete continuous beam bridge across the Chunhe Road Bridge from Wuhan to Shiyan with the finite element software,and the seismic response of the bridge under frequent and rare earthquakes is performed.Analysis,the main contents are as follows:(1)Explained the history of seismic research on bridge structures,the failure modes of prestressed concrete bridges under earthquakes,and the seismic design methods for frequent and rare earthquakes.(2)According to the "m" method,the spring element constraint is used to simulate the pile-soil interaction.A model considering the pile-soil interaction and the consolidation at the bottom of the pier is established.The influence of the pile-soil interaction on the dynamic characteristics of the bridge is studied.(3)Under the action of multiple earthquakes,according to the seismic design specifications of railway engineering,design response spectrum curves,and use the response spectrum method to analyze and compare the internal force and horizontal displacement response of the two models under the excitation of multiple earthquakes.(4)Using the three principles of wave selection,under the action of frequent earthquakes,referring to the relationship between the seismic wave frequency domain curve and the response spectrum curve,select seismic records with similar spectral characteristics to the site where the bridge is located.For the model considering pile-soil interaction,take The time-history analysis method calculates the seismic response of a prestressed concrete continuous beam bridge,and compares and analyzes the results of response spectrum analysis with time-history analysis.(5)An elastoplastic analysis of the bridge pier is simulated by Takeda’s tri-fold hysteresis model.Under the rare earthquake,plastic hinges unit within range of piers bottom is established.The state of plastic hinges at the bottom of the piers and the corner of the pier are analyzed.