Seismic Response Analysis Of Long Span Continuous Rigid Frame Bridge With High-Pier

With the development of transportation, continuous rigid-framed bridges were extended and applied in bridge engineering. These bridges are lifeline engineering, once destroyed, it will bring great economic losses. It is necessary to make an analysis to the seismic response of continuous rigid-framed bridges.In this thesis, taking Yujiang bridge as the research object, based on the basic theory of the seismic response analysis, two methods including response spectrum and time-history analysis of earthquake are applied to a continuous rigid-framed bridge. The main content in this thesis includes:1. Establishing four calculation models of the bridge; considering the influence of the pile-soil interaction and different substructure; analyzing the dynamic characteristics of the four models respectively.2. The seismic response of the four models were analyzed by response spectrum and dynamic time-history analysis methods. By changing the speed of the earthquake wave, the traveling-wave effect were analyzed.3. The influences of the vertical seismic effect, pile-soil interaction and traveling-wave effect of earthquake wave were discussed. The results of seismic response between the single thin-wall piers model and the double thin-wall piers model were compared.The main conclusions from above include:(1) Setting double thin-wall piers changes the sequence of the vibration mode of the bridge, reduces the natural frequency of the bridge, decreases the shear and moment of the bridge and increases the axial force of the piers.(2) The pile-soil interaction reduces the natural frequency and increases the displacement response of the bridge.(3) Compared with the results of seismic response obtained by response spectrum, the results obtained by time-history analysis method increases or decreases, we should adopt the larger result when design.(4) The internal force and the displacement of the bridge increases or decreases with the difference of the speed of the earthquake wave, we should choice the corresponding speed of the earthquake wave according to the actual ground soil when design.It is expected to give some references for practical seismic design of similar bridges.