Analytical approach for stress induced by internal pressure and temperature of underground compressed air energy storage in a circular lined rock cavern

As the stress induced by varying temperature and air pressure is important for the stability and durability of underground compressed air energy storage in lined rock caverns, an analytical approach for the induced stress is proposed. The cavern with a sealing layer, concrete lining and host rock is considered, the governing equations for temperature and air pressure of the cavern are established. The temperature field and air pressure during the operation period are obtained using the Laplace transform and the principle of superposition. Then the induced stress variations are determined analytically by employing a thermo-elastic model. The stress induced during a typical operation cycle is illustrated. The approach is subsequently verified by a coupled compressed-air and thermo-mechanical numerical simulation and by a previous study for temperature. Finally, the influence of temperature on the total stress and the impact of heat transfer coefficient are discussed. The results reveal that the caused tensile hoop stresses in the sealing layer and concrete lining are quite large. Moreover, the temperature has a non-negligible effect on the lined cavern for underground compressed air storage, while the hoop and longitudinal stresses are affected by the temperature to a larger extent than the radial stress. In addition, the heat transfer coefficient affects the cavern stress to a high degree.