Analysis on the Reliability and Prediction of Residual Life of Lining Structure of the Heat Supply Tunnel

Based on the field investigation on a heat supply tunnel in Beijing, a subset simulation method is adopted to calculate the safety reliability of the operating tunnel lining structure, and the failure probability and reliability index are obtained by improving the subset simulation method through optimizing the sample points of Hua-Wang point set. Compared with traditional Monte-Carlo method, it is found that the lower the failure probability, the more the precision and efficiency of improved subset simulation method. A new method for predicting the residual life of lining structures is established by the homogeneous Markov chains. In light of the carbonization law of concrete structure of heat supply tunnel, the concept and form of deterioration matrix are given, the ASI value of current state of lining structure is obtained, and Bayesian method is introduced to modify the prediction model by taking the current ASI as the boundary condition, with the results showing that the modified Markov chain model is applicable to predicting the residual life of lining structure of the operating heat supply tunnel.