The purpose of this project is to develop methods to simulate realistic design earthquake motions taking into account rupture process of active fault, traveling path and local soil conditions which include phase spectrum modeling of earthquake motion and interpolation of observed earthquake motions based on stochastic modeling of wave propagation field. We find that the phase characteristic of earthquake motion can be expressed by the fractional Brownian Process (FBP). Parameters defining this process are identified using observed earthquake motion phase and their physical characteristics are examined. We proposed a simple model to simulate earthquake motion phase based on FBP. The method for phase spectrum modeling has been implemented in the seismic design standard of Japan Railway Facilities
The main source of research fund is from the Grant-in-Aid for Scientific Research.