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Rock Mass Characterization For Excavations In Mining And Civil Engineering; Proceedings Of The International Workshop On Rock Mass Classification In Underground Mining
  • Published Date:
    5/1/2007
  • Language:
    English
Filetype[PDF-2.02 MB]


Details:
  • Personal Author:
    Barton, Nick, PH.D.
  • Description:
    When the Q-system was launched in 1974, the name referred to rock mass classification, with focus on tunnel and cavern support selection. Besides empirical design of support, the Q-value, or its normalized value Qc, has been found to correlate with seismic P-wave velocity, with deformation modulus, and with deformation. The Q-system provides temporary or permanent support for road, rail, and mine roadway tunnels and for caverns for various uses. It also gives relative cost and time for tunnel construction for a complete range of rock qualities. There are also indications that Q has captured important elements of the cohesive and frictional strength of rock masses, with Qc resembling the product of rock mass cohesion and rock mass friction coefficient.
  • Subject:
  • Collection(s):
    National Institute for Occupational Safety and Health
  • Main Document Checksum:
  • Supporting Files:
    No Additional Files
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