Seismic running safety of trains and a new type of seismic-isolation railway structure

Until now, seismic-isolation structures have not yet been applied in the railway field. The reason is that though a seismic-isolation structure can reduce the inertial force to the structure, the energy absorption causes big response displacement on the structure, which adversely effects the running safety of the trains supported by the structure. In this paper, a methodology for seismic running safety assessment is introduced, and a new type of seismic-isolation foundation is proposed, which can convert the seismic response displacement in the lateral direction of track to the longitudinal direction that has a less adverse effect on the running safety of the train. The isolation foundation is composed of FPS (Friction Pendulum System) slider, concave plate and guide ditch. Moreover, through model experiments and 3D numerical simulation, it is verified that the proposed foundation can keep both the effects of the seismic isolation and the running safety of the train during an earthquake.