Quality Evaluation of Slope Rock Mass after Excavation and Unloading

摘要

In a certain degree, rock mass quality deterioration after excavation and unloading would influence slope stability greatly. So it is very important to evaluate rock mass quality correctly and classify the rock mass for slope stability analysis. Based on the excavation of arch dam abutment slope of Bai Hetan power station, the rock mass quality was re-evaluated according to mechanical parameters of rock mass after excavation with the finite element method. The result shows that the RMR value of slope rock mass decreases linearly with the increase of unloading. Lastly, considering unloading as an important influencing factor, the evaluating parameters of the RMR method are revised, which is reasonable for engineering practice.