Seismic Response Analysis Of V-shaped Pire Rigid-frame And Tied Arch Combined Bridge

The V-shaped pier continuous rigid-frame bridge has feature that arch load together withV-shaped pier continuous rigid-frame,which is different from general beam-arch combinationbridge.There is so little reference material on research about such unique superstructure that itis very instructive significant to discuss its seismic response in order to analyze the dynamicresponse of the V-shaped pier continuous rigid-frame bridge under earthquake effect.Based onthe research of one bridge,the paper completely analyzed and discussed in details the bridge’sseismic response and vibration performance by MIDAS/Civil,and carried out some disciplineand conclusion as a source of reference for the seismic analysis of the kind bridge. The maincontents included:(1) Firstly，the paper discussed the importance and neeessity of seismic resistance onbridge constrctions,then consulting some domestic and foreign documents and materials aboutearthquake beam-arch combination bridge and seismic design,and summing up them to be anintroduction.(2) Deseribed the Process of the development of seismic resistance theory and currentsituation,then consulting the documents and materials about seismic response analysis ifbridge.Listing three methods of the seismic analysis,i.e.the Static method,the responsespectrum method and the dynamic time-history method.(3) Simply introducing the background of the brige and the finite-element method,usingMIDAS/Civil to establish model for analysis of dynamic characteristics.The results showedthat the out-plane stiffness is weaker than the in-plane stiffness for such type bridge.(4) To regard the ground motion parameter defined by spatial safety report as seismicexcitations input,doing dynamic response spectrum analysis,the results showed that in theLongitudinal Ground Motion,the maximum lateral displacement occurs in the vault,and themaximum vertical displacement occurs in the main girder of main span of1/4; this type of thebridge in seismic analysis cannot be ignored the effect of the vertical seismic action,and themost dangerous place of this kind of bridge is the arch foot and the root of inclined legs. (5) Based on the vibrational acceleration time-history input defined by spatialreport,doing seismic time-history response analysis,then makes a comparison of these twokind of methods, the results showed that in larger stiffness sites of the structure,thedisplacement of the response spectrum analysis and the Time-history Response Analysis isroughly equivalent; in smaller stiffness sites of the structure, the displacement of the responsespectrum analysis is larger than that of the Time-history Response Analysis,and the internalforce of time-history response analysis in general than the response spectrum analysis resultsof a large30%.