Seismic response analysis of a reinforced concrete continuousbridge considering coupling pounding-friction effect

To evaluate the coupling pounding-friction effect between bridge girders and retainers and its influence on bridge seismic response, a reinforced concrete(RC)continuous bridge is selected as the research object. Three bridge finite element(FE)models were built using OpenSees, in which the longitudinal and transverse pounding elements, as well as the transverse failure element of bearings were introduced. Based on this, the seismic response analysis considering the coupling pounding-friction effect was conducted for the continuous bridge subjected to bi-directional ground motions. Furthermore, the influential parameters were analyzed. The analysis results indicate that the coupling pounding-friction effect can alter the internal force distribution of the bridge structure and generate additional torsional force to bridge columns. The friction coefficient and longitudinal pounding gap size are two important factors. The appropriate friction coefficient and longitudinal pounding gap size can significantly reduce seismic response of girders, and effectively transfer part of the girder inertia force from the fixed columns to the sliding columns, which can reduce the seismic demands of the fixed columns and improve the seismic performance of continuous bridge structures.