STATISTICS IN AID OF INTERPRETING FRACTURE DATA

The probability distribution of fracture data from a rock mechanics test contains information about the effectiveness of the testing procedure and/or about the nature of the operating failure mechanism. The tensile strength of lac du bonnet granite forms a bimodal probability distribution when determined through line loading as in the Brazilian test. The same data obtained from three point bends tests are unimodal. The bimodality can in part be removed by distributing the line load over a finite area. Moisture has the anticipated effect in lowering both the average compressive and the average tensile strength of lac du bonnet granite. The reduction in strength however is not uniform within the probability distribution; the change is the largest at low and the smallest at high strength. Conversely, long-term loading is more damaging to the high strength members of the distribution. The large scatter of failure times in static fatigue experiments can in part be removed or even utilized when the probability distribution is instantaneous strength is taken into account. 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:
  • LAJTAI, E Z
• 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. 496-503

Subject/Index Terms

• TRT Terms: Bend tests; Compression; Conferences; Distributions (Statistics); Failure; Fatigue (Mechanics); Fracture mechanics; Granite; Information management; Information, data, and knowledge; Loads; Moisture content; Physical distribution; Rock mechanics; Rocks; Statistics; Strength of materials; Tensile strength; Tension; Test procedures; Testing
• Uncontrolled Terms: Fracture; Loading
• Geographic Terms: Canada
• ITRD Terms: 8018: Canada; 5532: Compression; 8525: Conference; 9016: Distribution (gen); 5520: Failure; 5579: Fatigue (mater); 4101: Granite; 8555: Information documentation; 5567: Load; 5920: Moisture content; 4154: Rock; 5757: Rock mechanics; 6555: Statistics; 5544: Strength (mater); 5502: Tension; 6288: Test method
• Subject Areas: Data and Information Technology; Freight Transportation; Geotechnology; Highways;

Filing Info

• Accession Number: 00452594
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• Files: ITRD, TRIS
• Created Date: Jul 31 1986 12:00AM