Development of an earthquake disaster simulator for railways

Railway systems are composed of many structures stretched continuously over a long distance. This system may cease to function entirely even if a limited part of it is damaged by an earthquake. It is therefore important to identify areas along a line which are vulnerable to such hazards, plan strategies for seismic countermeasures and implement them to minimize possible damage caused by an earthquake. For that purpose, an earthquake disaster simulator for railways has been developed to assess the seismic performance of an entire railway line. This simulator consists of three individual simulators: a seismic wave propagation simulator for deep ground between faults and bedrock, a seismic response simulator for the surface ground between bedrock and the ground surface, and a seismic response simulator for structures. To obtain large-volume analysis models for simulation, data archives for faults, the ground and structures, and modeling tools for constructing analysis models automatically using the archive data have been also developed. These tools have made it possible to conduct earthquake disaster simulations for railway lines stretching over several hundred kilometers. In addition, visualization tools were developed to display results on a Geographic Information System and create images of damaged structures so that non-experts can understand possible risks in earthquakes. Trial simulations of past earthquakes were implemented using the simulator and it was confirmed that simulation results correspond to actual damage.