In connection with the measurements carried out during the construction of the Bourse Experimental Gallery, the "Compagnie de Prospection Geophysique Francaise" (the French Geophysical Exploration Company) conducted some non- destructive dynamic tests. A seismic prospecting device was positioned in boreholes in front of the drilling face and 20 series of measurements were made over 7 months. They showed the influence of drilling machines on rocks. Beyond A decompressed zone there exists a compressed ring, the characteristics of which improve up to a 5-diameter heading and remain even after 7 months. Tests on samples enabled formulae to be derived for forecasting average stress values. /TRRL/

  • Corporate Authors:

    Comite Francais de Mecanique des Roches

    Rue du Grand Moulin 19
    Saint Etienne,   France 
  • Authors:
    • Lakshmanan, J
  • Publication Date: 1973-7-15


  • French

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 33-41
  • Serial:
    • Issue Number: 5

Subject/Index Terms

Filing Info

  • Accession Number: 00129652
  • Record Type: Publication
  • Source Agency: Central and Regional Labs of Bridges & Highways,Fr
  • Files: ITRD, TRIS
  • Created Date: Apr 7 1976 12:00AM