Research On Static And Seismic Performance Analysis Of Smaill-radius Curved Continuous Rigid-framed Bridge With High-piers

There are a wide range of features of small-radius curved continuous rigid-framed bridges with high piers,including:graceful structure style,driving comfort and uncomplicated construction,and so on.With the greater investment of the state on railway construction,the application of such bridges are becoming wider and wider,which is urgently required enhancement to cognitive performance about bridges with this type.Hence,it is conduct overall studies about this type bridges.The developments and history researches of small-radius curved continuous rigid-framed bridges were reviewed in the beginning of the thesis,and the mechanical characteristics were summarized in the thesis.This thesis was based on Shengquan No.l Bridge,which is a small-radius curved continuous rigid-framed bridges with high piers.The static and dynamic performances of the bridge in construction stage and operation stage were analyzed while the impacts of design parameters on the structure responses under earthquake were discussed.At first,a finite element model of the bridge through the beam element was established by MIDAS/CIVIL 2015,while the pile-soil interaction was considered.Based on the model,internal forces and deformations of the bridge at contruction stage were studied as well as change laws of the force at the cantilever root section.Also,the static behaviors were analyzed under actions including dead load,live load,temperature load,centrifugal force,wind force,braking force and their combinations at the operation stage.Then,the natural frequency analysis were carried out through Lanczos model at the operation stage.Meanwhile,the responses of the bridge suffered from seismic excitations via different directions were analysed by response spectrum analysis.Also the results derived from the response spectrum analysis and time-history analysis in one-way excitation were compared from each other.At last,the sensitivity analysis of design parameters on the seismic responses,including different radius of curvature and different pier heights were systematacially performed by means of the response spectrum analysis,while the change laws of seismic responses varied with different design parameters were investigated.There are some clear understanding about the static and dynamic performances of small-radius curved continuous rigid-framed bridges,which is supposed to provide references on the seismic design and study of the similar structures.