Stability analysis of underground water-sealed oil storage caverns in China：A case study

The stability of underground water-sealed oil storage caverns is of great importance for safe excavation and operation. To analyze the scope of the failure zone and underground cavern stability accurately, a new method was developed that integrates the rock tunneling quality index Q-system and stability graph method with 3D laser scanning and numerical simulation. The point cloud data were obtained by 3D laser scanning, and the cavern model was built by using DIMINE software, which directly shows the 3D shape of the cavern. The rock mass physical and mechanical parameters and the corresponding stability coefficients were obtained based on Q-system and stability graph method. The plastic zone distribution and deformation characteristics of surrounding rock were analyzed through numerical simulation. Then, the corresponding relationship between caving zone and plastic zone was determined by comparing the numerical simulation results with the 3D laser scanning contour. The new method provides a reliable way to analyze the stability of the underground water-sealed oil storage cavern and also will helpful to design or optimize the subsequent support.