Abstract: The stress of support system and the load-bearing characteristics between shotcrete and rock are research focuses in the excavation of underground oil storage in rock caverns. In this paper, the deformation and stability of cavern and the stress condition of the support system are studied though simulating the excavation of underground caverns by finite element software ANSYS. Furthermore, the work condition of shotcrete and rock is discussed by incorporating thin layer element in the simulation with the bond strength between surrounding rock mass and shotcrete into consideration. Research reveals that the deformation of surrounding rock is relatively small with linear elastic deformation due to good integrity and high strength. The support system should be completed in time to prevent from local falling resulting from joints. Sensitivity analysis shows that under the action of water pressure, when the bond strength between surrounding rock and shotcrete is less than 0.6 MPa, shotcrete begins to separate from the side walls, and when bond strength is less than 0.5 MPa, more separated area appear even in the vaults. Therefore the construction quality of shotcrete should be noted and field adhesion test should be intensified.

Key words: underground oil storage in rock caverns, support system, load-bearing characteristics, shotcrete, bond strength