High Pier Span Continuous Rigid Frame Bridge Seismic Performance Study

High-pier long-span continuous rigid frame bridge has been widely used in bridge engineering. Altough main span and height of the piers continuously breaks new records, high-pier long-span continuous rigid frame bridge's seismic code has lagged behind its practical application, thus restricting the further development of bridge construction. Therefore, the seismic response analysis of high-pier long-span continuous rigid frame bridge and the understanding of its dynamic characteristics in the course of earthquake is of important significance in providing a scientific basis for the vibration resistance and safety design of such bidges.Based on the basic theory of seismic response analysis, this thesis conducts the seismic response analysis to the Mangjiedu continuous rigid frame bridge. The main contents are as follows:1) Using finite element software MIDAS, the author establishes a spatial finite element model of the bridge structure, and carries out the modal analysis. By analyzing and comparing the vibration characteristics of different models of pier height, the author sums up the effect of pier height on the dynamic characteristics of long-span continuous rigid frame bridge.2)By conducting the response spectrum analysis to seismic characteristics of structure and elastic time history analysis to high-pier long-span continuous rigid frame bridge, and making a comparison between the calculation results of the two methods, the author finds out their respective seismic response differences to high-pier long-span continuous rigid frame bridge and meanwhile takes into account the effect of vertical earthquake on seismic response of bridges.3) By varying the height of the piers and comparing them with the seismic response analysis results of the finite element model of actual project cases, the author sums up the effect of pier height on the seismic response of long-span continuous rigid frame bridge.4) Finally, the author presents some suggestions for seismic calculations and designs of high-pier long-span continuous rigid frame bridge structure based on the seismic response analysis results.