Stability Assessment of Surrounding Rock of Underground Cavern Complexes Based on Energy-Dissipation Model

Stability analysis of surrounding rock is a complicated and always experience depended work in underground excavation engineering. In this paper, An Energy-Dissipation Model for stability assessment of surrounding rock of underground cavern complexes in hydropower plant is proposed. Firstly, the general FEM procedure to simulate underground excavation is put forward. Then, the Energy-Dissipation Model is expounded by introducing certain damage indexes of rock mass such as the distribution and volumes of plastic, crack and rebounding zone and the magnitude of ´Plastic Dissipation Energy´ that is a representative index employed to indicate the general disturbance degree of the stress condition of rock mass subjected to excavation, which is significant to assess the stability of surrounding rock. Finally, a case study is further illustrated with the stability assessment of surrounding rock of underground houses of a large-scale hydropower plant. And it is shown that the proposed method is rational and the Energy-Dissipation Model could effectively reflect the general stability status of surrounding rock.