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Japan, Yokohama - jp/15


  New 4.1 km metro line from Yokohama station to downtown Motamachi via the Minato Mirai 21 area, scheduled to be in service 2003. Hazama Corporation undertaking 450 m-long twin-tunnel section between Kenchomae and Kitanaka stations using high performance mud pressurised 7.15 m-diameter DPLEX shield developed by NKK. This design of decentred multi-shaft shield accommodates circular, rectangular and horseshoe sections and boasts reduced cutter torque compared with conventional single-shaft machines. The makers say it is cheap to run and easy to dismantle. January 2000.