Underground Space Development and Tunneling Technology

摘要

(1) Modern methods related to the development of underground space originated from the sewage tunnel in Paris and the subway system in London in the 19th Century. (2) Railway systems are vital means of transportation for passengers in large cities. Railway systems have to change their modes from the mass rapid transit (MRT) system for the suburban or inter-city commuters to the intermediate MRT or light rail transit (LRT) for the intra-city commuters. (3) The suburban MRT adopts normally a long train system that runs mostly above ground from suburban areas to city centers, and in the city the medium- or small-capacity subway or LRT systems are adopted for the intra-city transportation. Large cities having large populations need to have a large or medium capacity transportation means such as subway systems. (4) Developing countries need subway or other effective railway systems with modal shift ideas. It is estimated that the most of major cities in Asia will have subway systems within a half of 21st century (5) Underground roads and highways also become necessary in the heavily congested urban areas as can be seen in Boston and Tokyo that provide environmental solutions. (6) The modal shift concept is necessary not only for the physical transportation of goods, but also for water transport and reservoirs' management as well as for the passengers transport. Mechanical handling or transporting systems have to be developed together with the network-system development. (7) Networking has become necessary and common not only for railways, but also for roads, shopping malls, pedestrian walkways, car parking, etc. Networking will prove to be extremely important in the future for physical transportation and for sewage and trash transportation, treatment, and/or disposal. It produces the maximum possible efficiency throughout the entire city as part of city management. (8) Technology of the deep underground, up to 100 m below the surface, is becoming important for soil and soft rock grounds, especially in Japan. (9) The need for large-diameter tunnels and large-sized caverns, for road traffic and other purposes, will continue to increase. For shield tunnels and urban NATM technologies, a diameter span of 20 m is the goal for the near future. (10) Large tunnels and caverns will be needed in the future. Technical solutions will include new large-scale outer shell reinforcement.