2020 Volume 20 Issue 3 Pages 3_1-3_20
The seismic ground motion records observed in the Kashiwazaki-Kariwa Nuclear Power Station were used to evaluate a regional three-dimensional velocity structure model that would be used for long-period ground motion prediction. First, the velocity structure model evaluated by the National Institute of Advanced Industrial Science and Technology was modified by incorporating the underground structure information obtained by geophysical exploration of the site and surrounding area. Next, the earthquake ground motions with a period of more than 2 seconds due to medium or small earthquakes occurred near the source regions of the huge scenario earthquake were simulated by the three-dimensional finite difference method. The effectiveness of the modified model was evaluated by the reproducibility of the waveforms and the response spectra.
