Life-cycle reliability analysis of shield tunnels in coastal regions: emphasis on flexural performance of deteriorating segmental linings

Abstract

In contrast to reinforced concrete (RC) structures on land, RC shield tunnels in coastal regions deteriorate rapidly after their construction because of the combined effects of multiple mechanical and environmental stressors. In this paper, by considering the coastal hazards associated with chloride and the impacts of hydrostatic pressure, a novel approach is presented to estimate the life-cycle structural performance of a shield tunnel that has undergone deterioration due to chloride-induced steel corrosion. Deterioration processes in segmental linings are investigated via corrosion-accelerated experiments on individual segments, and the combined effects of corrosive agents and loads are emphasized. Monte Carlo simulation is used to estimate the time-variant failure probability of shield tunnels in a marine environment. In an illustrative example, the effects of structural location, hydrostatic pressure and material properties on the life-cycle reliability of shield tunnels are investigated.

Keywords:

• Reinforced concrete shield tunnel
• hazard assessment
• chloride
• hydrostatic pressure
• deterioration
• corrosion initiation
• time-variant failure probability

Acknowledgements

The experimental testing of segmental specimens presented in this paper was conducted in the MOE Key Laboratory of Transportation Tunnel Engineering of Southwest Jiaotong University, People’s Republic of China.

Disclosure statement

No potential conflict of interest was reported by the authors.