The Vibration Signal Analysis of Debris Flow in Taiwan

Yi-Min Huang ； Yao-Min Fang ； Tien-Yin Chou ； Chen-Yang Lee ； Hsiao-Yuan Yin

《Geotechnical Hazard Mitigations: Experiment, Theory and Practice—Proceedings of the 5th International Conference on Geotechnical Engineering for Disaster Mitigation and Rehabilitation》 2017年 (2017/10) Pp. 149-161

https://doi.org/10.6140/9789864371419.201710.0013

摘要

Debris flow has become a common disaster in Taiwan in recent years since the impacts of extreme weathers has been aggravated. To protect people from the debris flow disasters, a monitoring and warning system was developed by Soil and Water Conservation Bureau (SWCB). There are two types of sensors in the monitoring system: direct and indirect options. The rain gauge, which is an indirect option, measures rainfall in a monitoring station, and used as a debris flow warning factor in the disaster response. In contrast, the geophones (short period seismograph) and broadband seismographs are direct options of debris flow monitoring, and they were used to record the vibration signals generated by debris flows. In this paper, the signal analysis of debris flows was performed by applying FFT, wavelet transform, and Gabor transform. The comparison of the analysis results indicated the characteristic signal of a debris flow was evident in the frequency range of 10~40 Hz, and the signal of front end of debris flow was identified in the lower frequency range of 0~10 Hz. The possibility of applying geophones and broadband seismographs to debris flow warnings was also discussed in this paper.

關鍵字

Debris flow ； Vibration signal analysis ； Geophone ； Broadband seismograph