Long-term leakage at the tunnel joint induces significant tunnel deformations, which in turn aggravates the joint leakage. A finite element model (FEM) model with a defined leakage element incorporated in a segmental joint is developed to investigate the evolution of joint leakage and deformation. Subsequently, a series of parametric analyses are conducted to reveal the time-dependent law of joint opening and leakage variation with leakage location, water head, and waterproof capacity based on Qiongzhou Strait tunnel. The results show that the interaction between joint opening and leakage undergoes a dynamic evolution process during the long-term operation of the tunnel. It is found that the joint opening on the extrados is much more critical and hazardous than that on the intrados, and the synthetic action of water head and waterproof capacity can remarkably delay the development of joint opening and leakage. For Qiongzhou Strait tunnel, the joint opening on the extrados occurs after at least 30 years of initial leakage at the springline and increases to 1.28 mm, and the leakage rate increases from 0.909 × 10−4 m3/d to 1.508 × 10−4 m3/d after 120 years. It is suggested that the waterproof capacity and initial leakages near the springline should be strictly controlled to ensure the long-term safety of the tunnel.
Long-Term Evolution of Joint Leakage and Joint Opening for Shield Tunnel in Soft Soils Deep under Seabed
KSCE J Civ Eng
KSCE Journal of Civil Engineering ; 26 , 3 ; 1396-1406
2022-03-01
11 pages
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch