RIB-IN-ROC FOR LARGE UNDERGROUND EXCAVATIONS

Rib-in-Roc is a means of supporting large span underground openings by the use of ribs of reinforced concrete and rock bolts constructed around the cavern before it is excavated. The technique provides a rib-like construction of concrete arches and rock-bolting that forms a reinforced structure integrated with the rock mass itself. Theoretical examinations and model testing of the Rib-in-Roc method are described. It is noted that a low-horizontal primary stress will result in an initially non-compressed and loose volume of rock mass above the roof of the cavern. A self-supporting static roof vault will gradually establish itself through an inward radial displacement of the rock giving rise to tangential compressive stresses following the curved roof contour. The Rib-in-Roc method has demonstrated to the following: Rock chambers with very large spans are now possible; their size and shape are less dependent on rock quality at the site than has formerly been the case; in-situ information on rock characteristics obtained from the rib tunnels will be invaluable for an accurate design of the chamber; and, safety is increased at the working face. By adopting the number of ribs, their shape and position to the strength, structure and stresses of the rock mass, the Rib-in-Roc method offers a possibility for constructing large underground openings with spans of 50mm. Bolts, reinforced ribs, and the rock mass around the opening form together a reinforced ring which acts whether the rock has elastic or plastic properties.

  • Availability:
  • Corporate Authors:

    Foundation Publications Limited

    7 Ongar Road
    Brentwood CM15 9AU, Essex,   England 
  • Publication Date: 1978-1

Media Info

  • Features: Figures;
  • Pagination: p. 26-44
  • Serial:
    • GROUND ENGINEERING
    • Volume: 11
    • Issue Number: 1
    • Publisher: EMAP CONSTRUCT LIMITED
    • ISSN: 0017-4653

Subject/Index Terms

Filing Info

  • Accession Number: 00173892
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Files: ITRD, TRIS
  • Created Date: May 31 1978 12:00AM