Reliability analysis of underground water-sealed storage caverns stability: Method and application

The reliability analysis method considers the uncertainty of rock parameters, making the stability analysis of underground engineering more accurate. A reliability analysis method applicable to assess the stability of underground water-sealed storage caverns was proposed in the study. In the method, the performance functions were established from the perspectives of the plastic zone and cavern displacement by modifying the elastic–plastic solution of the circular tunnel. The reliability index and probability of failure were calculated using the first-order reliability method and the reliability analysis results calculated by the proposed method and the Monte Carlo method was used to verify the correctness of the proposed method. Finally, the reliability analysis method was used to evaluate the reliability of an underground water-sealed storage caverns stability in southern China. The reliability index and probability of failure of the storage caverns with different support ways were obtained and the optimization design of the support system was determined based on the reliability analysis results.