Effect of Seismic Isolation Bearings on the Potential Pounding between Adjacent Girders for Long-Length Girder Bridge Systems

Abstract

Research on seismic-isolated bridges concerning potential pounding between adjacent units remains limited to date, especially for long-length girder bridge systems consisting of several long- span girder bridges where the wave passage effect is of great significance. To investigate the effect of seismic isolation bearings on the potential pounding between adjacent girders considering the wave passage effect, a finite element model of a bridge system consisting of two box-girder bridges and one long-span hybrid truss-box girder bridge is developed. The results show that under uniform excitations the seismic isolation bearings can reduce the relative displacement at expansion joints and thus improve the performance against pounding. However, the wave passage effect can increase the deformation demands of the expansion joints and improve the probability of pounding even though seismic isolation bearings are used, especially for the low apparent wave velocities.