This article discusses relative reliability of three main methods of estimated tunnel support, RMR, Q and RMi using fieldwork and rockmass classification as well as independent laboratory tests. The rock being tested is located along the alignment of a 6-km road tunnel proposed as an alternative to a section of surface road. Convenience and reproducibility are the main factors in the evaluation and the main reason for using empirical methods. All three were rated roughly the same in terms of convenience. However, each method created variations among observers for some parameters. Using values expressed in a range rather than a single absolute can help minimize the influence of these variations. The Q system was found to be the most sensitive to influence, but the Q support chart was found to be the most convenient to use for estimating tunnel support and was also the simplest, since it needed only field mapping. The study found that all three systems had advantages.

  • Availability:
  • Supplemental Notes:
    • Page range: pp 45, 47-48
  • Corporate Authors:

    Polygon Media Limited

    Tubs Hill House, London Road
    Sevenoaks, Kent TN13 1BY,   United Kingdom 
  • Authors:
    • Nilsen, B
    • Shrestha, G L
    • Panthi, K K
    • Holmoy, K H
    • Olsen, V
  • Publication Date: 2003-5


  • English

Media Info

  • Features: Figures; References; Tables;
  • Pagination: 3 p.
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00962213
  • Record Type: Publication
  • Source Agency: UC Berkeley Transportation Library
  • Files: BTRIS, TRIS
  • Created Date: Sep 2 2003 12:00AM