SHEAR STRENGTH OF JOINTS FOR ESTIMATING THE STABILITY OF ROCK SLOPES

SKJAERFASTHET AV SPREKKER FOR BESTEMMELSE AV FJELLSKRAANINGS-STABILITET

The ability to estimate the shear strength of rock joints provides for a rapid assessment of the stability of existing and future rock slopes. Expensive and time consuming direct shear tests can be avoided if two simple index tests are performed. First a direct shear test is carried out on a block containing a typical joint through the whole rock. The block is tilted until the joint is so steeply inclined that the upper half slides down the joint plane. This angle of inclination taken together with the dimensions of the block, gives a measure of the surface roughness, smooth joints may slide at angles of only 30 degrees, while rough joints may not slide before 70 or 80 degree inclination. The second index test is designed to measure the compressive strength of the joint walls, which will often be lower than that of the fresh rock if the joints are weathered. The strength is measured with a Schmidt hammer, which is a simple device for recording the rebound of a spring loaded plunger after its impact with the joint surface. /TRRL/

  • Availability:
  • Corporate Authors:

    Norwegian Geotechnical Institute

    Postboks 40 Tasen
    Oslo 8,   Norway 
  • Authors:
    • Barton, N
  • Publication Date: 1978-7

Language

  • Norwegian

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00174144
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Report/Paper Numbers: Rpt. No. 112
  • Files: ITRD, TRIS
  • Created Date: Jul 29 1978 12:00AM