Earthquake Sensor

Abstract

A new concept earthquake sensor was developed utilizing spectral intensity (SI) as a measurement value. The acceleration sensing part and signal conditioning part are all integrated in one body as a transducer. A real-time SI calculation algorithm was newly developed and proven by actual simulated earthquake waveforms with a three-axis exciter bench. A liquefaction judgment algorithm was also developed based on acceleration signals and integrated into the SI sensor. Thus, the first all-in-one SI sensor with liquefaction judgment was realized. With this sensor, a new earthquake disaster prevention system for gas supply, Supreme, was developed and introduced into operation around the area of Tokyo Bay, Japan.