State-of-the-art tunnelling technology to create urban underground space – Japanese challenge

Abstract

Japanese shield tunnelling technologies have been developed firstly in mid 1950s to provide essential infrastructures of good quality such as sewerage and water network, power and cable network system, and subway system in the heavily populated urban area. Slurry shield and EPB shield are some of the typical achievement of Japanese contribution to the world tunnelling society. Then in 1980s, the technologies were further developed with vast experiences of boring through variety of geology under severest tunnelling conditions like alluvial and diluvial water-bearing unstable soils, small tunnel cover, excavation close to important structures, to bore underground reservoir/channel and road tunnel with larger diameter of 10 m or over. Successful construction of the 10 km long Trans-Tokyo Bay tunnel by slurry shield with excavation diameter of 14.14 m using variety of automated tunnelling systems is the typical example. Currently to meet strong public demands to build infrastructures with least expensive life-cycle cost due to the Japanese recession from 1990s, quite variety of shield tunnelling technologies such as non-circular boring, one pass lining, watertight and durable lining, no secondary lining and many others. The paper introduces the state-of-the-art shield tunnelling technologies and market trends statistically, and two representative tunnelling projects, which could contribute to the world tunnelling society in the near future. (A). Reprinted with permission from Elsevier. For the covering abstract see ITRD E124500.