Abstract: Underground lined gas storage reservoirs for compressed air energy storage (CAES) are subjected to expanding internal pressure, which often results in cracking in the lining and yielding in the surrounding rock. However, research on the cracking and yielding characteristics of lined reservoirs remains relatively insufficient. Drawing upon the multi-layer thick-walled cylinder theory and considering the stratification and equivalence of steel lining, concrete, steel reinforcement, and surrounding rock, this study simplifies cracked concrete as an orthotropic layer and models the surrounding rock using the Mohr-Coulomb yield criterion and non-associated flow rule. Analytical solutions for stress and displacement during the stages of elastic deformation, brittle cracking, and plastic yielding are derived accordingly. Furthermore, by integrating the improved Dong Zheren crack calculation method, the numerical solution for the radial displacement of the lining’s outer wall is employed to replace the traditional shell approximation, facilitating the simultaneous prediction of the maximum crack width in the lining and the radius of the plastic zone in the surrounding rock. Additionally, this study analyzes the influence of factors such as storage reservoir radius, internal pressure, steel lining thickness, concrete strength grade, and thickness on the cracking behavior of the lining and the yielding characteristics of the surrounding rock. Finally, an in-depth discussion is conducted on the cracking behavior of the lining and the yielding characteristics of the surrounding rock. Results indicate that within the typical engineering parameter range defined in this study, the internal pressure of the storage reservoir, the quality grade of the surrounding rock, and the in-situ stress are the primary factors affecting the cracking width of the lining, while the in-situ stress is the main factor influencing the cracking and yielding ranges. The lining rapidly cracks and fails when internal pressure exceeds a certain threshold. The cracking and yielding ranges primarily occur between 0 and 10 meters and gradually increase with rising gas storage pressure. The findings provide theoretical support for analyzing the cracking and yielding characteristics of underground lined storage reservoir structures.

Key words: compressed air energy storage, underground lined storage reservoir, orthotropic, lining cracking, rock mass yielding