Energetic Criterion of Entering Acceleration in Progressive Failure Process of Bedding Rockslide: A Case Study for Shanshucao Landslide

Bedding rockslide is the most common slope disaster. It is of great significance to study its progressive failure process and establish prediction criteria for disaster prevention and mitigation. Taking Shanshucao landslide in Zigui as an example, on the basis of field investigation and indoor rock test, the basic mechanical parameters of landslide were estimated by JRC-JCS model and GSI method. The progressive failure process of landslide was simulated by FLAC^3D, and the development law of deformation and failure of bedding rockslide was analyzed. Based on the principle of energy conservation and virtual work, the energetic criterion for accelerated deformation of bedding rockslide is proposed. The results show that the landslide mass of Shanshucao is progressively destroyed from the rear edge to the front, the accumulated total displacement value of the trailing edge deformation increases continuously, the locking effect of the front cutting layer makes the deformation decrease rapidly. When approaching failure, displacement of the leading edge develops from front to back, transfixion of sliding face occurs quickly. The strain curve along the sliding direction of the landslide can be approximated as a "S" curve, which develops downhill with progressive failure. Taking the kinetic energy increment of the landslide mass greater than 0 as the energetic criterion for accelerated deformation of the landslide, the results are consistent with the geological evolution of landslides and are in good agreement with those of FLAC^3D simulation.