CRITERIA FOR DETERMINING THE CRITICAL STRESS OF ROCKS IN COMPRESSION

The commonly used criteria, the most notable of which is the onset of material dilation, for predicting the critical stress of rock have been shown to give incorrect values. An incremental Poisson's ratio criterion recently proposed by the authors was found to give more realistic estimates. A microscopic study of the mechanism of fracture showed that cracks of approximately equal length continue to develop up to maximum stress. Strength failure was primarily related to an increase in crack density and not so much the length of individual cracks. Tests were performed on sandstone, marble and concrete and, in general, similar conclusions were observed for each material. Methods for estimating impending failure in the case of cyclic loading are also discussed. (a). The number of the covering abstract of the conference is IRRD abstract no. 213776. /TRRL/

• Supplemental Notes:
  • Presented at the First Australian Conference on Engineering Materials.
• Corporate Authors:

  University of New South Wales

  School of Civil Engineering, Anzac Parade
  Kensington, New South Wales  Australia  2033
• Authors:
  • Dhir, R K
  • SANGHA, C M
• Publication Date: 0

Language

• English

Media Info

• Features: Figures; Photos; References; Tables;
• Pagination: 8 p.

Subject/Index Terms

• TRT Terms: Compression; Concrete; Cracking; Forecasting; Fracture mechanics; Loads; Poisson distributions; Poisson ratio; Repeated loads; Rocks; Sandstones; Strength of materials; Stresses; Tests
• Uncontrolled Terms: Fracture
• Old TRIS Terms: Poissons ratio
• ITRD Terms: 5532: Compression; 4755: Concrete; 5211: Cracking; 132: Forecast; 5567: Load; 5924: Poisson's ratio; 4154: Rock; 4104: Sandstone; 5544: Strength (mater); 5575: Stress (in material); 6255: Test
• Subject Areas: Geotechnology; Highways; I43: Rock Mechanics;

Filing Info

• Accession Number: 00129581
• Record Type: Publication
• Source Agency: Transport and Road Research Laboratory (TRRL)
• Report/Paper Numbers: Conf Paper
• Files: ITRD, TRIS
• Created Date: Apr 7 1976 12:00AM