An analytical solution for elastoplastic responses of a lined rock cavern for compressed air energy storage considering excavation and high internal pressure

An analytical solution for elastoplastic responses of an underground lined rock cavern for compressed air energy storage under initial hydrostatic pressure and high internal air pressure is proposed. In the analytical solution, the stress paths during cavern excavation and operational stages are considered. A numerical simulation is performed by using the finite element software Abaqus to verify the analytical solution. The concept of “high-pressure plastic zone” is proposed and the evolution of “high-pressure plastic zone” is analyzed. Furthermore, taking the occurrence of “high-pressure plastic zone” and failure of the sealing layer as the critical states, the calculation methods for critical internal pressure pcr1 and ultimate internal pressure pu are proposed. Sensitive analyses are conducted to study the key parameters affecting the “high-pressure plastic zone” and the critical internal pressure. The research indicates that the proposed analytical solution can accurately predict the elastoplastic responses of an underground lined rock cavern. The radius of “high-pressure plastic zone” are mainly related to the surrounding rock quality, magnitude of air internal pressure and buried depth of cavern. The critical internal pressure pcr1 and ultimate internal pressure pu are mainly related to the surrounding rock quality, cavern size, buried depth and thickness of concrete layer.