A NEW DEVELOPMENT OF THE LNEC STRESS TENSOR GAUGE

A new development is presented of the LNEC stress tensor gauge, in the form of a hollow cylinder 2 mm thick (i.d. 31 mm, O.D. 35 mm), with electrical resistance strain gauges embedded midway from the inside to the outside surface. The recent plastic gauge, to be installed like its solid forerunner in a standard EX borehole, is claimed to substantially reduce the incidence of practical situations where the gauge to rock bond fails on stress-relief overcoring. Analytical expressions are deduced and checked, which enable the complete state of stress in the studied rock mass to be determined from the nine strains measured with the gauge.

• Supplemental Notes:
  • Presented at the 3rd Congress of the International Society for Rock Mechanics, Denver, Colo., 1974.
• Corporate Authors:

  National Civil Engineering Laboratory, Portugal

  Avenida do Brasil
  Lisbon 5,   Portugal 
• Authors:
  • Rocha, M
  • Silverio, A
  • Pedro, J O
  • Delgado, J S
• Publication Date: 1974

Media Info

• Features: Figures; References;
• Pagination: 11 p.

Subject/Index Terms

• TRT Terms: Boreholes; Mass; Resistance (Electricity); Rocks; Stress gages; Stress relieving; Tensor analysis
• Uncontrolled Terms: Rock mass
• Subject Areas: Geotechnology; Highways;

Filing Info

• Accession Number: 00125394
• Record Type: Publication
• Report/Paper Numbers: No. 455 Memoria
• Files: TRIS
• Created Date: Oct 18 1975 12:00AM