The excavation of the 18.5km long Qinling rail tunnel in north west China was recently completed. For the first time in China, imported tunnel boring machine (TBM) technology was used by local workers on a major scheme. This article reports on a visit to the tunnel's remote site, to find out how a combination of TBM and drill+blast technology was used to achieve its impressive excavation. The tunnel has two roughly parallel single-track tubes, about 30m apart. Tube 1 to the east has 7.7m internal diameter, and was excavated by Wirth open face TB 880 E TBMs driving from the north and south portals. Tube 2 is horseshoe shaped, and was constructed first as a parallel 6.2m high, 4.8m wide pilot tunnel by drill+blast; it will be enlarged later. The ground consists mainly of hard rock, including gneiss and granite. The TBMs being used are the largest in China, and have 8.8m diameter. This article describes the TBMs used, describes the tunnelling works from the north and south portals, and briefly discusses the lessons learned from the sometimes very slow progress made by the TBMs. The TBMs performed well whenever ground conditions allowed. Wirth went through a tough learning experience, and the Chinese also had a long and steep learning experience as they had to cope with several unfamiliar technologies.

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  • Corporate Authors:

    Miller Freeman

    Calderwood Street
    London,   United Kingdom  SE18 6QH
  • Authors:
    • McCormack, S
  • Publication Date: 1999-12


  • English

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Filing Info

  • Accession Number: 00788440
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD
  • Created Date: Mar 3 2000 12:00AM