Analysis on Rock Mass Around an Underground Crude Oil Storage Caverns in Containment of Groundwater Considering Fluid Solid Coupling

Abstract

Triaxial compression tests have been performed to determine the properties of the rock mass around an unlining underground crude oil storage caverns which is the first one in China. The execution situation of the tunnel project and the seepage law of groundwater are taken into account; the stress and the seepage field around the tunnel in different working states are simulated by applying Comsol around a underground crude oil storage caverns.According to the test results, it was found that the excavation process may arise the local damage,the extension of the excavation induced loose zone ranges from 0 to 15.6 m, depending on the buried depth of the caverns. According to numerical simulation results, the crown settlement and stress concentration is depended on the buried depth and the water pressure distribution after the excavation of the main cavity. This research results can provide the reference for analysis on the stability of the underground cavities under low stress level and on the water sealed underground petroleum storage rock caverns.