Elastic and elastoplastic analysis of surrounding rock in CAES chambers considering excavation‐induced centripetal exponential reduction in mechanical properties

Abstract Currently, there is a lack of research on the impact of excavation damage on the stability of underground compressed air energy storage (CAES) chambers. This study presents a comprehensive analytical framework for evaluating the elastic and elastoplastic stress fields in CAES chambers surrounding rock, incorporating excavation‐induced centripetal reduction of rock stiffness and strength. A proposed model introduces exponential reduction functions for the deformation modulus and cohesion within the excavation disturbed zone (EDZ), deriving analytical solutions for both elastic and elastoplastic stress distributions. A case study of a practical engineering project validates the theoretical formulations through comparative analysis with numerical simulations, demonstrating strong consistency in stress field predictions. The main findings indicate that the EDZ causes a significant non‐monotonic variation in the elastic hoop stress distribution. While it does not significantly affect the range of the plastic zone, it reduces the permeability and bearing capacity of the surrounding rock, highlighting the necessity of integrating the centripetal reduction of mechanical properties and strictly controlling excavation‐induced damage in the design practice. Furthermore, this study provides a new approach for the selection of lining materials and structural design for CAES chambers: the radial stiffness smoothly increases to match the EDZ surrounding rock stiffness, and the cohesion exceeds that of the surrounding rock, which can significantly optimize the overall system's stress distribution. This study provides valuable insights and references for the selection of excavation methods, stability assessment, and support structure design for CAES engineering, and holds significant importance for improving the CAES technology system.