Seismic Response Analysis Of (86.5+152+86.5)m Box-girder Bridge With Corrugated Steel Webs

Compared with ordinary prestressed concrete girder bridges,the box girder bridge with corrugated steel webs has the advantages of light weight,convenient construction,beautiful shape and high economic benefits,which is widely used in highway engineering and railway engineering.As an important part of the national traffic line,the seismic performance of bridge structures has attracted more and more attention.Therefore,it is very important to study the seismic performance and isolation technology of the box girder bridge with corrugated steel webs.This paper takes the main bridge of Pingshan to Zanhuang expressway(86.5 +152 + 86.5)m South-to-North Water Diversion Bridge as the research object,and uses the finite element software Midas Civil to establish two kinds of finite element models,ordinary basin type rubber bearing is used to one and friction pendulum seismic isolation bearings is used to another one.Models are established to dynamic characteristic analysis and seismic response analysis under the E1 and E2 earthquake excitation of the bridge,the main work is as follows:(1)This paper expounds the importance of structural seismic design,the development of corrugated steel web plate box girder bridge,and the structural characteristics of this type of bridge,at the same time,the existing seismic isolation technique is introduced.(2)Two models without and with seismic isolation design are established by using Midas Civil finite element software.The dynamic characteristics of the two models are analyzed and compared.(3)By using the response spectrum analysis method,the internal force response and displacement response of the two models with and without seismic isolation under the action of E1 earthquake are analyzed,and the results are compared and analyzed to study the isolation effect of the friction pendulum seismic isolation bearings on such kind of bridge.(4)Under the action of E2 earthquake,three seismic wave records are selected according to the wave selection principle,and the time-history analysis method is applied to analyze the time-history response of the two models,so as to obtain the isolation effect of the friction pendulum seismic isolation bearings.A seismic wave record is selected to analyze the parameter sensitivity of the isolation effect of friction pendulum seismic isolation bearings in three aspects:pier height,bearing radius and site conditions.(5)In order to further clarify the seismic performance of this kind of bridge,the elastoplastic analysis of the no isolation model is carried out,under the action of E2 earthquake,which is improved by one level.This paper puts forward design suggestions and reinforcement measures.