An ultrasonic velocity borehole logger has been developed for use in small diameter boreholes drilled in rock for probing ahead of tunnels. The paper gives details of its design and construction and examples of its use in logging boreholes drilled in a laboratory trial and in an underground stone quarry. Two special features of the logging tool are that the transducers are mechanically pressed against the rock in the borehole wall and therefore no liquid is needed in the borehole to provide a coupling for the signal, and that the whole tool has been made compact enough to fit into a 56 mm diameter borehole. The instrument measures the compressional wave velocity of the rock, which may be interpreted to provide a qualitative indication of rock properties. In addition a method of deriving the rock strength from the velocity is suggested and demonstrated for the two test boreholes. Recommendations for developing the prototype into an instrument for routine use are made. (Author/TRRL)

  • Corporate Authors:

    IPC Science and Technology Press Limited

    IPC House, 32 High Street
    Guildford, Surrey  England 
  • Authors:
    • WEST, G
    • NEW, B M
  • Publication Date: 1981-3

Media Info

  • Features: Figures; Photos; References;
  • Pagination: p. 67-71
  • Serial:
    • Ultrasonics
    • Volume: 19
    • Issue Number: 2
    • Publisher: Butterworth Scientific Limited

Subject/Index Terms

Filing Info

  • Accession Number: 00335026
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD, TRIS
  • Created Date: Sep 16 1982 12:00AM