IN SITU STRESS MEASUREMENTS IN ANISOTROPIC ROCK

The purpose of this paper is to discuss how to account for rock anisotropy when measuring in situ stresses by overcoring with instrumented devices such as the CSIRO hollow inclusion cell or the U.S. Bureau of Mines (USBM) gauge. The rock is described as an isotropic, a transversely isotropic or an orthotropic material. The computation of in situ rock stresses with the two devices mentioned above depends on the anisotropic rock character, the degree and type of rock anisotropy, the orientation of the rock anisotropy with respect to the hole in which the devices are located, and, for the CSIRO cell only, dimensionless parameters describing the relative deformability of the rock with respect to the deformability of the cell material. Using these parameters, the paper addresses the following problems: the effect of the degree and type of rock anisotropy on in situ stress determination; the error involved in neglecting rock anisotropy by assuming isotropy; the error involved in neglecting the geometry and properties of the CSIRO cell by assuming that its strain gauges are positioned directly on the walls of pilot holes, and how this error is affected by the rock anisotropy. (TRRL)

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/01489062
• Corporate Authors:

  Pergamon Press, Incorporated

  Headington Hill Hall
  Oxford OX30BW,    
• Authors:
  • Amadei, B
• Publication Date: 1984-12

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 327-338
• Serial:
  • Intl J of Rock Mech & Mining Sci & Geomechanic Abs
  • Volume: 21
  • Issue Number: 6
  • Publisher: Pergamon Press, Incorporated
  • ISSN: 0148-9062

Subject/Index Terms

• TRT Terms: Anisotropy; Boreholes; Deformation; Errors; Field tests; Measurement; Measuring instruments; Modulus of deformation; Rocks; Strain gages; Stresses; Structural analysis
• Uncontrolled Terms: Anisotropic
• Old TRIS Terms: Anisotropy; In situ stresses; Overcoring
• ITRD Terms: 6155: Apparatus (measuring); 5711: Bore hole; 5595: Deformation; 6440: Error; 6226: In situ; 5917: Isotropic; 6136: Measurement; 4154: Rock; 5562: Strain gauge; 5575: Stress (in material); 5573: Stress analysis
• Subject Areas: Geotechnology; Highways; I43: Rock Mechanics;

Filing Info

• Accession Number: 00394621
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• Files: ITRD, TRIS
• Created Date: Jul 31 1985 12:00AM