Seismic response of urban viaducts with different bearings

Abstract

In order to research the influence of bearing arrangement on the seismic response of urban viaduct, the 4 × 30 m standard span and C ramp bridge of the main line are taken as the engineering background. The SeismoStruct software is used to establish and analyse the seismic responses. For the standard span of the main line, under the same ground motion input, the internal force of the pier for the seismic isolation system is reduced by about 1 to 4 times compared with the ductile seismic system, but the displacement of the piers or the bearings are relatively large, and the overall cost of the structure is high. For the C ramp bridge, the shear force, axial force and pier displacement with all lead-core rubber bearings are lower than those with fixed bearings. From the perspectives of structure seismic response, post-earthquake repair and engineering economy, it is suggested that the viaduct of the standard span should adopt the plate type rubber bearing, and the C ramp bridge should adopt the fixed bearing.