CHARACTERISTIC ANALYSIS OF THE SEISMIC SIGNAL FOR GRANULAR FLOW IMPACTING THE GROUND

Owing to the unprompted and short time span of natural hazards, such as rockfalls and rockslides, it is difficult to conduct real-time monitoring and rapid event analysis. Correspondently, environmental seismology can well solve those defects. Based on the analysis of emitted seismic signal, the characteristics of rockfalls or landslides including volume, duration time and kinetics parameters can quickly be obtained. We conducted a series of laboratory experiments simulating the process of granular flow impact the ground. Then, the correlations between the seismic parameters and the initial condition and kinetic parameters of granular flow were studied via the analysis of recorded seismic signal during experiments. Experimental results showed that:(1)The bandwidth of seismic signal gradually decreases as the volume of granular flow increases; (2)The peak ground acceleration, duration time, Arias intensity and the seismic energy are gradually increasing with the increasing of granular volume, which have good correlations; (3)The ratio between the seismic energy and the potential energy lost range from 3.09×10^-2 to 7.2×10^-1 and mostly increases with increasing in the granular flow volume. In this paper, we established the relationship between the characteristic parameters of landquake and the initial conditions as well as kinematic parameters of granular flow, which provides a theoretical basis for the monitoring and emergency response of mountainous rockfalls and landslides.