TUNNELLING THE CHANNEL

This article describes how the excavations of the Channel Tunnel were carried out. Most of the tunnel was drilled through Lower Chalk Marl, a very favourable tunnelling rock, which is relatively impermeable, has moderate strength, and is highly self-supporting. From the start, there was a strong pressure to finish the excavation within its 60-month civil construction programme. To remain on schedule, the work had to progress from as many points of attack as possible. From end to end, the 50.5km long tunnel has 151.5km of tunnelling, ranging from 4.8m internal diameter for the central service tunnel to 7.6m internal diameter for both the running tunnels. Additional excavations included: (1) two large undersea crossover structures; (2) three large complex undersea pumping stations; and (3) many cross tunnels and overhead ducts. 147km of tunnelling was excavated by 11 full-face tunnel boring machines, and lined with a one-shell segmental lining largely of high-strength precast concrete. The UK tunnellers were able to advance at up to 1000m per month per machine, but geological conditions were more difficult on the French side.

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  • Corporate Authors:

    Reed Business Information, Limited

    Quadrant House, The Quadrant
    Brighton Road
    Sutton, Surrey  United Kingdom  SM2 5AS
  • Authors:
    • Wallis, S
  • Publication Date: 1993-12-9

Language

  • English

Media Info

  • Pagination: p. 18-21
  • Serial:
    • CONTRACT JOURNAL
    • Publisher: Reed Business Information, Limited
    • ISSN: 0010-7859

Subject/Index Terms

Filing Info

  • Accession Number: 00724260
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD
  • Created Date: Aug 19 1996 12:00AM