Abstract: The safety of the lining structure and the air tightness of the underground gas storage cavern under cyclic high internal pressure are the dual challenges faced in the construction of compressed air energy storage (CAES) caverns, and are the key factors determining the success or failure of CAES power stations. The purpose of underground caverns serving as CAES gas storage containers is to fully utilize the bearing capacity of the surrounding rock. A CAES gas storage cavern consists of a sealing layer, a lining system, and the surrounding rock. The surrounding rock should be both rigid and tough, the lining both flexible and ductile, and the sealing layer flexible and durable. The "flexibility" of the sealing layer and the lining may refer to the flexibility of the material itself (e.g., polymer flexible sealing layer and flexible concrete lining), or to the adoption of flexible or ductile structures (e.g., crack-control design and deliberate crack-inducing design to enhance the toughness of reinforced concrete lining, and profiled steel lining to increase the flexibility of the steel-lining sealing layer). This paper reviews the design status and research progress of sealing and lining structures for CAES caverns and offers prospects for future development.

Key words: compressed air energy storage, underground cavern, bearing capacity of surrounding rock, lining structure, sealing layer, research progress