Study on amplification characteristics of seismicity at dam sites using monitored acceleration data, affected by disturbance of the nearby existing cavern

摘要

The earthquake monitoring for Kuzuryu dam has been conducted since its completion. Due to the aging deterioration and following update of the monitoring system, the current system is arranged to the underground powerhouse in addition to the dam crest and both dam abutments. Around 200 earthquake data accumulated so far clarify the dynamic behavior of the dam and its foundation. The dynamic amplification characteristics of the dam and its abutments reflect the characteristics of these materials and configurations. The possible influence on the monitored acceleration due to the existence of the underground powerhouse nearby the dam is examined referring to the numerical simulation of the seismic propagation as well as the frequency analysis. The disturbance due to nearby existing underground structure on the seismic wave amplification is confined in its surrounding area and negligible in other part of the dam foundation.