UNDERGROUND UMBRELLA PROTECTS TUNNEL DRIVE IN UNSTABLE SANDS

A patented method is described which involved installing an arch of horizontal bored tubes (that later formed the crown of the excavated tunnel) to provide support for a sand stratum before driving an underground section of railway in Paris. The umbrella arch resembles a curved grid, the bars of which comprise steel tubes installed just outside the tunnels periphery parallel to its axis, i.e. either horizontally or inclined to conform to the grade of the subsequent tunnel. Installation accuracy is essential, so as to ensure that the lining of the tunnel comes into contact with the inner face of the tube arch after excavation and the gaps between lining and ground are minimized. To meet the requirements of the scheme, the design took into account the section of the tubes, the thickness, the mechanical characteristics of the steel used in their manufacture, and their spacing.

  • Availability:
  • Corporate Authors:

    Foundation Publications Limited

    7 Ongar Road
    Brentwood CM15 9AU, Essex,   England 

    Wells (Edward) and Sons, Limited

    143/145 Camberwell New Road
    London SE5,   England 
  • Publication Date: 1976-3

Media Info

  • Features: Figures;
  • Pagination: 3 p.
  • Serial:
    • GROUND ENGINEERING
    • Volume: 9
    • Issue Number: 2
    • Publisher: EMAP CONSTRUCT LIMITED
    • ISSN: 0017-4653

Subject/Index Terms

Filing Info

  • Accession Number: 00135924
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Oct 6 1976 12:00AM