Strain behavior of a granite and a graywacke sandstone in tension
Westerly granite and Lance graywacke sandstone were deformed with one of the principal stresses tensile at the same time that the principal strains were monitored. Both rocks exhibited inelastic behavior prior to failure. Pronounced dilatancy and softening in shear took place in the granite. When Young's modulus varied, it did so continuously between compression and tensile stress states with no apparent discontinuity at zero axial stress, implying that cracks played the same role in tension as in compression. Failure was observed whenever the tensile stress exceeded a critical value, in agreement with predictions from Griffiths' failfure criterion. The sandstone exhibited approximately twice as much strain per unit stress change as the granite and showed evidence of grain-to-grain movement as well as crack closure, results consistent with comparisons determined earlier when all stresses are compressive.
- Research Organization:
- Lawrence Livermore National Laboratory, University of California, Livermore, California 94550
- OSTI ID:
- 5985039
- Journal Information:
- J. Geophys. Res.; (United States), Vol. 87:B9
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
GRANITES
FRACTURE MECHANICS
STRAINS
SANDSTONES
DEFORMATION
EXPERIMENTAL DATA
GEOLOGIC MODELS
TENSILE PROPERTIES
DATA
IGNEOUS ROCKS
INFORMATION
MECHANICAL PROPERTIES
MECHANICS
NUMERICAL DATA
PLUTONIC ROCKS
ROCKS
SEDIMENTARY ROCKS
580300* - Mineralogy
Petrology
& Rock Mechanics- (-1989)