Stability evaluation of surrounding rock in lined rock caverns under cyclic thermal-mechanical conditions for compressed air energy storage

The lined rock cavern (LRC) serves as a key facility for Compressed air energy storage (CAES) with significant large-scale potential, yet its long-term Stability evaluation under cyclic loading poses a major challenge. To address this, a Fatigue mechanics model accounting for mean principal stress effects on geomaterial yielding is applied, better capturing their cyclic degradation. Thermo-mechanical coupling simulations over 100 operational cycles reveal that cavern temperature follows a “rise–fall–fall–rise” cycle pattern, stabilizing after about 30 cycles. Concurrently, maximum principal stress in the surrounding rock rises and stabilizes after similar cycles, increasing tensile failure risk at the crown during storage, especially in weaker rock. Moreover, rock pressure-bearing capacity gradually declines with cycling. Notably, controlled concrete-lining cracking can enhance Stress transfer to the rock, improving system stability, whereas excessive cracking may overload the rock. This study offers a predictive framework and practical guidelines for designing and operating stable underground CAES systems. • A rock fatigue constitutive model incorporating mean principal stress effects was adopted. • Analyzes cyclic thermo-mechanical response of CAES lined rock caverns • Calculate the stress transfer coefficients for structural layers of the lined cavern • Investigate the influence of concrete cracking on stress transfer capacity