Abstract:
Compared with conventional tunnels, there are some varying features regarding the design of underwater tunnels, and the underwater tunnel can be constructed with different methods. The key points to consider in the design are demonstrated in terms of geological conditions, link conditions, environmental conditions and construction costs. As for the mined underwater tunnel, it is thought the depth of the rock cover, the type of water-proofing and drainage will directly affect tunnel safety and economy. Based on demonstration and analysis, the method and principles used to determine tunnel overburden, the type of water-proofing and drainage are presented. For the determination of water pressure, which has been a tough problem in tunnel design, corresponding calculations are given considering different methods of water-proofing and drainage. In addition, construction methods to ensure tunnel durability and safety are presented by using a specific tunnel as an example.