Calculation method for limit burial depth of compressed air energy storage lined cavern considering structural load sharing

This paper presents a calculation method for the limit burial depth of compressed air energy storage (CAES) lined caverns incorporating load-sharing effects. A mechanical model based on three-layer thick-walled cylinder theory is established to analyze stress distribution and load-sharing ratios among the steel layer, concrete lining, and surrounding rock. Combined with the rigid conical limit equilibrium model, a formula for limit burial depth is derived. Parametric analysis investigates the influence of cavern radius, steel and concrete lining thicknesses, concrete strength, maximum storage pressure, rock mass grade, and in situ stress on burial depth. Results indicate that the surrounding rock bears the predominant load (approximately 75% on average), followed by the concrete lining (approximately 20% on average) and steel layer (approximately 5% on average). Cavern radius, concrete lining thickness, and rock mass quality significantly affect load distribution, while cavern radius, rock grade, and in situ stress critically influence burial depth. These findings provide practical guidance for the optimal design of CAES lined caverns.