Study on the Failure Development Process and Energy Evolution of Rock Slope

The development of landslide often accompanied by accumulation, transfer and dissipation of energy. To understand the energy evolution in rock slope may be beneficial to the clarification of landslide mechanism, which can be took as consultation for landslide hazard assessment and prediction of runout distance of sliding material. Considering numerical method, the details of energy evolution inside the rock mass during the process of slip surface development and movement of debris after rock slope collapse. In this study, two kinds of simplified models were created by distinct element method. One is a cube with given slip surface composed by disconnected small crack. The model was used to simulate development of slip surface. Another is a single cube sliding along a flat wall. The model was used to simulate the moving behavior of single debris after rock slope collapse. A series of model with different inclination angle of wall and material property were created to represent different type of landslide and collision behavior respectively. For each model, the energy data were collected from selected elements which distribute uniformly inside the model. The results show that during the development of slip surface, the cracks propagate and then form the slip surface. The strain energy inside the rock mass near the crack accumulates continuously and drops rapidly soon after the crack propagates through the rock mass. After the slip surface be formed, the slope collapse and the potential energy transfers into kinetic energy. Then the frictional energy and damping energy generated by interaction between debris or between debris and mountainside. The debris travels along slope with high inclination angle rebounds higher after hit the bottom of mountainside, but has lower travel distance than ones travels along slope with lower inclination angle. The debris with lower strength tends to break into smaller pieces, and generates more frictional and damping energy due to higher interaction frequency between small pieces.

Keywords: Rock slope, Landslide mechanism, Energy evolution, Distinct element method