[MTT39-P01] Shaking table tests on seismic response of microbarograph
Keywords:Sensitive Microbarograph, Shake table, instrument response of microbarograph by vibration
Earthquake of Mj3.7 occurred at a depth of 5.2km, and its seismic signal was observed by both the microbarograph and accelerometer. The distance between the epicenter and the observation site is approximately 20 km. This case showed that in start shaking the microbarograph recorded similar waveforms to that of the accelerometer, and pressure change was much greater than gravitational pressure. To learn component of pressure change in detail, we vibrated vertically and horizontally the above microbarograph and accelerometer on the shake table. This microbarograph is attached a coiled tube tipped with air joint at air hole as a dumper, in order not to destroy inside mechanism by a mechanical shock while installing a microbarograph in a case and excessively torque while tightening air joint. We introduce the result of vibration experiment, such as the effect of a tube by fixed the tube to the shake table and instrument response by covered a tube to block outside air.
Acknowledgement: This study was supported by the Joint Usage/ Research Center program of Earthquake Research Institute, the University of Tokyo. We use the Vibration testing system managed by the Earthquake Research Institute. We are grateful to Prof. A. Araya for the vibration testing system operation.