Abstract：
The Nanjing Weisan Road river-crossing tunnel has some of the most complex geological conditions and engineering technical difficulties of any existing and under-construction large-diameter slurry shield tunnels. During the construction process, the large-diameter slurry shield machine has successfully passed hrough shallow ground as well as soft upper and hard lower mixed ground, and has directly passed under the ventilation shaft. Furthermore, hyperbaric chamber intervention technology with a saturated helium-oxygen mixed gas was successfully introduced for this project. In this paper, the key construction technologies used in this project are studied regarding engineering characteristics and construction difficulties; the safety concept and excavation principles for the shallow ground, soft upper and hard lowe rmixed ground are proposed; and a complete set of safe, reliable technology for extra-large diameter slurry shield launching and saturated hyperbaric chamber intervention is summarized, providing a significant reference for the development of extra-large diameter slurry shield-driven tunnel technology.
2015, Vol. 52 