Novel excavation systems remove rock by four basic mechanisms: (1) melting and vaporization; (2) thermal spalling; (3) mechanical breakage, and (4) chemical reactions. The energy required to remove rock by these novel systems is much greater than that for conventional excavations; consequently, these novel systems will find widespread application only in conjunction with conventional drills and excavators. In this case the novel devices will be used to cut slots or holes in the rock, thereby weakening the rock and enhancing the conventional rock removal system. Lasers and electron beams have demonstrated that they can effectively cut narrow kerfs in rocks, but improved focusing systems will be required before they find widespread application. Rocket drills and electric drills currently being developed drill some hard rocks faster than conventional drills. Explosive drills being developed indicate potential for drilling granite and other hard rocks at rates up to 36 metres per hour. New systems for changing the bit cutting elements in deep wells without pulling the drillstem from the hole are under development. High pressure water jet drills and tunnelling machines have indicated potential for drilling and excavating 2 to 5 times faster than conventional systems. As a result of the extensive work underway, it appears that some of these novel excavation systems will find commercial application within the next two years.

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  • Corporate Authors:

    Pergamon Press, Incorporated

    Headington Hill Hall
    Oxford OX30BW,    

    Pergamon Press, Incorporated

    Maxwell House, Fairview Park
    Elmsford, NY  United States  10523
  • Authors:
    • Maurer, W C
  • Publication Date: 1977-12


  • English

Media Info

  • Features: Figures; Photos; References; Tables;
  • Pagination: p. 99-112
  • Serial:
    • Underground Space
    • Volume: 2
    • Issue Number: 2
    • Publisher: Pergamon Press, Incorporated
    • ISSN: 0362-0565

Subject/Index Terms

Filing Info

  • Accession Number: 00174019
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Report/Paper Numbers: Analytic
  • Files: ITRD, TRIS
  • Created Date: May 31 1978 12:00AM