2. A triaxial shear test was performed on a well-drained sand sample. The normal stress on the failure plane and the shear stress on the failure plane, at failure was determined to be 6,300 psf and...

Extracted text: 2. A triaxial shear test was performed on a well-drained sand sample. The normal stress on the failure plane and the shear stress on the failure plane, at failure was determined to be 6,300 psf and 4,200 psf, respectively. a. Determine the angle of internal friction of the sand. b. Determine the angle of failure plane. c. Determine the maximum principal stress.