Seismic Ground Response

In an event of an earthquake, source, path, and site characteristics as well as soil-foundation-structure interaction strongly a ects the seismic action to structures. Studies to understand these characteristics and their in uence, and risk evaluation considering the degree of in uence of each aspect, are conducted to reduce seismic disasters.

Directional dependence shown in the horizontal-to-vertical spectral ratios of observed microtremor near the south-west corner of the Kyoto Imperial Palace (Heterogeneity of deep subsurface structure such as a slope in the east-west direction can be inferred from the gure)