Strength criterion for rocks subjected to cyclic stress and temperature variations

The strength of rocks subjected to cyclic stress and temperature variations must be determined to ensure the stability of caverns for underground compressed air energy storage. This paper proposes a strength criterion for rocks subjected to cyclic stress and temperature variations; the proposed criterion is based on the least energy dissipation principle and the rock damage induced by cyclic stress and temperature effects. The cyclic uniaxial stress-temperature tests and uniaxial compression tests after cycling are conducted to validate preliminarily the proposed criterion. The applicability of the proposed strength criterion and the influence of damage factor selection are discussed. The proposed strength criterion has a clear physical meaning and only involves four parameters to be determined. The predicted rock strengths are in good agreement with the laboratory test results, confirming the applicability of the proposed criterion. The proposed strength criterion can degenerate into certain existing criteria. Moreover, the damage factor is suggested to be calculated with the use of the peak secant modulus when the proposed strength criterion is applied.