THE EFFECT OF JOINT CONFIGURATIONS ON THE STRENGTH AND DEFORMABILITY OF MODEL ROCK MASSES

The mechanical behavior of a jointed rock was investigated by means of triaxial test with gypsum plaster models. The effect of joint configuration (joint spacing and joint inclination) on the strength and deformability or rock mass was investigated by analyzing all the test results of the present investigation carried out earlier by others as part of a large program of model studies. This research led to the following conclusions. The strengths of any models, either jointed or intact, increased with confining stress within the range from 0 psi to 1850 psi. The plaster used to make the models is believed to have been transformed from a brittle to a ductile behaving material at a confining stress of about 1850 psi. The strengths of model jointed rock were smaller than that of intact model in the range of confining pressure at which tests were performed. The joint configurations had a great influence on the strength of a rock mass at low confining stresses, but little or no effect at high confining stresses. The strengths of specimens that failed by sliding along pre-existing joint planes appeared to be independent of joint spacing for a given joint inclination. Portions of this document are not fully legible.

• Corporate Authors:

  Massachusetts Institute of Technology

  Department of Civil Engineering, 77 Massachusetts Avenue
  Cambridge, MA  United States  02139
• Authors:
  • Motoyama, H
  • Hirschfield, R C
• Publication Date: 1971-6

Media Info

• Pagination: 189 p.

Subject/Index Terms

• TRT Terms: Rock mechanics
• Subject Areas: Geotechnology; Railroads;

Filing Info

• Accession Number: 00054330
• Record Type: Publication
• Source Agency: National Technical Information Service
• Report/Paper Numbers: FRA-RT-73-25 Final Rpt
• Contract Numbers: DOT-C-85-65
• Files: TRIS
• Created Date: Jun 10 1974 12:00AM