Simulation Analysis for the Nonlinear Seismic Response of Seismically Isolated Continuous Bridge

According to the behavior of seismically isolated continuous bridges, the bidirectional nonlinear characteristics of lead rubber bearing are taken into account by using two orthogonal nonlinear level spring elements. Based on the FEA software, the analysis models of seismically isolated and non-isolated continuous bridges are established. And the nonlinear seismic response for these analysis models is carried out under the function of the reasonably chosen seismic motion. The analytic results indicate that the natural period of seismically isolated bridge can be prolonged to avoid the principal period of ground and the seismic energy of structure can be efficiently consumed by the hysteretic energy dissipation of lead rubber bearing. So the response of bridge structure can be reduced to make sure most of the components work in the elastic phase and the structure can be well protected.