Valid constitutive relations for rock are required to enable accurate calculation of shock wave propagation and ground motion in the earth. Experiments have been performed on Cedar City tonalite to determine the stress-strain properties under a variety of loading paths. A servo-controlled triaxial test apparatus, which permits the axial and radial stresses to be varied in a pre-programmed manner, was utilized in the test program. Tests were performed using hydrostatic, uniaxial strain, constant confining pressure and constant stress ratio proportional loading load paths. Axial and radial stresses and strains were recorded during the test. It was found that the stress-strain behavior of this material is dependent only on the magnitude of the stress. Complete stress-strain curves are reported for single and cyclically loaded specimens. Author
Technical rept. Oct 68-May 70,
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