EFFECT OF STRAIN RATES FROM 0,01 TO 10 PER SEC IN TRIAXIAL COMPRESSION TESTS ON THREE ROCKS

Room-temperature, compression tests at strain rates from 0,01 to 10 per sec have been run on charcoal granodiorite to 0.45 gpa confining pressure and on berea sandstone and Indiana limestone to 0.25 gpa confining pressure. For each rock at each confining pressure, the differential stress at failure is relatively constant up to a strain rate of 1 per sec and apparently increases abruptly above this strain rate. Dynamic analysis of the testing apparatus indicates that the apparent sudden increase in strength is due to machine inertia and does not reflect a real increase in the strength of the rocks. Taking inertia into account, the actual failure stresses of the three rocks are relatively independent of strain rate between 0.01 and 10 per sec. In the same interval, the strains at which the unconfined rocks begin to fragment tend to be lower at higher strain rates. The combination of decreasing strains and relatively constant stresses with increasing strain rate suggests that the energy necessary to fragment the unconfined rocks is lower at higher strain rates. (TRRL)

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/00207624
• Corporate Authors:

  Pergamon Press, Incorporated

  Headington Hill Hall
  Oxford OX30BW,    
• Authors:
  • Blanton, T L
• Publication Date: 1981-2

Media Info

• Features: Figures; Photos; References; Tables;
• Pagination: p. 47-62
• Serial:
  • International Journal of Rock Mechanics and Mining Science
  • Volume: 18
  • Issue Number: 1
  • Publisher: Pergamon Press, Incorporated
  • ISSN: 0020-7624

Subject/Index Terms

• TRT Terms: Compression; Compressive strength; Deformation; Equipment; Failure; Inertia (Mechanics); Limestone; Pressure; Rock crystals; Rocks; Sandstones; Strain (Mechanics); Strength of materials; Stresses; Tests; Triaxial shear tests
• Uncontrolled Terms: Strain rate; Triaxial compression; Triaxial testing machine
• ITRD Terms: 5532: Compression; 4023: Crystal; 5595: Deformation; 3674: Equipment; 5520: Failure; 5491: Inertia; 4131: Limestone; 5412: Pressure; 4154: Rock; 4104: Sandstone; 5544: Strength (mater); 5575: Stress (in material); 6255: Test; 5566: Triaxial
• Subject Areas: Geotechnology; Highways; I43: Rock Mechanics;

Filing Info

• Accession Number: 00335224
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• Files: ITRD, TRIS
• Created Date: Oct 28 1981 12:00AM