The Seismic Response Analysis Of The Corrugated Steel Web PC Box Girder Bridge

Corrugated steel web PC is a new type of continuous rigid frame bridge, the box girder have replaced previous concrete web with corrugated steel web plate, which improve the property of the structure as a whole. With engineering background of a corrugated steel web plate box girder bridge, the finite element software Midas was used to analyze the seismic response of the bridge.This article studies the three span continuous rigid frame bridge. Firstly, the finite element model of bridge was established by Midas, as well as the simulation of boundary conditions and the analysis of upper structure variable cross-sections. We studied the static characteristics of the built finite element model, the shear force and bending moment of the bridge were less than the allowable values under action of constant load combination, short-term load combination and standard load combination.Secondly, analyzing the vibration mode and intrinsic frequency of bridge, and adopting multiple Ritz vector method to extract the top 20 order vibration mode and intrinsic frequency of the structure. According to the vibration mode in the percentage of the quality, it was known that the first order or second order is the main vibration mode of the bridge.The seismic response of bridge was analyzed by response spectrum method and time history analysis method. It was shown that the bridge was greatly influenced by horizontal seismic, the longitudinal and transverse displacements of the top of the bridge pier are the main factors. The bridge piers were double limb thin-wall piers, the top displacement of left and right limb pier of the main pier was different, but with the little difference. The maximum displacement of the upper structure was located in the center of bridge. The probability of maximum shear force located in the bottom of the right limb pier on the side of left pier under the response spectrum method with different seismic wave and time history analysis method with different loading was highest.Comparing the calculation results of two methods, it shew that the results of time history analysis was generally larger than 80% of results of response spectrum analysis, which meets the detailed rules for the earthquake resistant design for highway bridges.