Numerical simulation of the underground storage cavern using FDEM

Underground storage cavern has been increasingly exploited as it has many advantages such as reducing investment, economizing land use and improving safety compared with storage above the ground surface. We employ the hydromechanical coupled FDEM to simulate the excavation and operation phases of the underground storage cavern with a water curtain system (WCS), taking into consideration the natural discrete fracture network (DFN). The simulation results captured the propagation and slipping of the pre-existing DFN during the excavation and operation process. We quantitatively evaluate the containment performance based on the water inflow and pore pressure distribution. This study provides new insights into evaluating the stability of cavern-surrounding rock masses and containment performance of underground storage caverns.