Seismic response of continuous girder bridge with laminated rubber bearing considering friction sliding

To investigate the seismic performance of bridges laminated rubber bearing considering friction sliding, quasi-static tests on five laminated rubber bearings and one lead rubber bearing were conducted. The similarities and differences of mechanical properties between laminated rubber bearing considering friction sliding and lead rubber bearing were compared and analyzed, such as force-displacement hysteresis curve, equivalent stiffness, equivalent damping ratio and hysteretic energy dissipation. Taking a continuous girder bridge as example, the influences of bearing fraction sliding on pier bottom curvature ductility coefficient, pier bottom shear force, bearing displacement and residual displacement and hysteretic energy dissipation of piers and bearings were analyzed by nonlinear time history analysis. The seismic performance of bridge considering friction sliding was investigated, and the application of laminated rubber bearings considering friction on a small and medium span continuous bridge was verified. The results show that the hysteretic mechanical model of laminated rubber bearing considering friction sliding can be described by bilinear hysteretic model; after loading displacement is greater than 200%, the hysteretic energies of laminated rubber bearings and lead rubber bearing are closer; the laminated rubber bearing considering friction slipping can dissipate significant amount of earthquake energy, which relates to the gap between main girder and stop block, and the determination of the gap is related to the spectral characteristics of the earthquake, which should be noticed in the seismic design. © 2016, Editorial Department of China Journal of Highway and Transport. All right reserved.