Discrete Element Modeling of the Nayong Rock Avalanche, Guizhou, China Constrained by Dynamic Parameters from Seismic Signal Inversion

A rock avalanche that destroyed 23 houses and killed 35 people occurred on 28 August 2017, Nayong, SW China. Combined with the dynamic parameters from seismic signal inversion, a discrete element model, MatDEM was used to determine the rock avalanche's kinematic behavior. Although the dynamic process obtained through inversion will be disturbed by factors, such as rockfall from the source area, by comparing the velocity of rock avalanche versus horizontal distance traveled, the best combination of parameters was selected from different values given. The dynamic process obtained by modeling was compared with the nearest seismometer frequency distribution spectrum, showing that the dynamic process is in good agreement with those parameters inverted from seismic signals. The simulation results show that the movement process lasted for nearly 40 s, with a maximum speed of 40 m/s. This model of selecting parameters contributes to explain the dynamic processes of similar rock avalanche more accurately and is of great significance to the hazard prediction in the karst area.

Automated summary

A rock avalanche in Nayong, SW China on August 28, 2017 destroyed 23 houses and killed 35 people. By combining dynamic parameters from seismic signal inversion, a model was used to determine the rock avalanche's kinematic behavior. Comparing the simulation results with seismic signals showed good agreement, indicating the potential for more accurate hazard prediction in karst areas.