PERMEABILITY, PERCOLATION AND STATISTICAL CRACK MECHANICS

The permeability of sands and soils seems to be adequately described by Darcy's law, but the permeability of rocks is complicated by a number of factors related to the probability of crack intersections. During the last few years a statistical theory of fragmentation has been developed, which has been successful in explaining the observed behaviour of rocks. In this paper, a theory of permeability is developed which draws on the concepts employed in previous work. The permeability involves three factors, the average fluid flux per crack, the number of cracks per unit area, and the fraction of cracks that are not isolated. Probabilistic ideas are used in connection with the hydrodynamic theory of flow through a single crack to develop an integral expression for permeability. The result has the form of Darcy's law for anisotropic media. Although the current work is motivated by the need to develop optimized oil-shale retorts, it is believed that the theory can be applied to a variety of other problems. For the covering abstract of the symposium see TRIS 452576. (Author/TRRL)

• Supplemental Notes:
  • Proceedings of the 23rd Symposium on Rock Mechanics, Issues in Rock Mechanics, University of California, Berkeley, California, August 25-27, 1982.
• Corporate Authors:

  American Institute of Mining, Mettalurgy & Petroleum Engineers

  345 East 47th Street
  New York, NY  United States  10017
• Authors:
  • Dienes, J K
• Conference:
  • Proceedings of the 23rd Symposium on Rock Mechanics, Issues in Rock Mechanics, University of California, Berkeley, California, August 25-27, 1982.
• Publication Date: 1982

Media Info

• Features: Figures; References;
• Pagination: p. 86-94

Subject/Index Terms

• TRT Terms: Anisotropy (Physics); Conferences; Cracking; Failure; Flow; Fluid dynamics; Mathematical models; Oil shales; Percolation; Permeability; Powders; Probability; Rock mechanics; Rocks; Statistics; Theory
• Uncontrolled Terms: Anisotropic
• Old TRIS Terms: Anisotropy; Probabilistic factors
• ITRD Terms: 8525: Conference; 5211: Cracking; 5430: Flow (fluid); 5917: Isotropic; 6473: Mathematical model; 5921: Permeability; 4154: Rock; 5757: Rock mechanics; 4315: Seepage; 6555: Statistics; 9078: Theory
• Subject Areas: Data and Information Technology; Geotechnology; Highways;

Filing Info

• Accession Number: 00452580
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• Files: ITRD, TRIS
• Created Date: Jul 31 1986 12:00AM