Example Problems

Example Problem 1: A dry sand sample failed in a direct shear test with a normal stress of 100 kPa and a shear stress at failure of 60 kPa. Determine the angle of internal friction.

Example Problem 2: A consolidated-undrained (CU) triaxial test was conducted on a saturated clay.

Calculate the effective angle of internal friction ($\phi'$).

Example Problem 3: A direct shear test was performed on a sample of dry, normally consolidated sand. The normal stress applied during the test was $150 \, kPa$, and the shear stress at failure was $86.6 \, kPa$. Calculate the angle of internal friction of the sand and the major and minor principal stresses at failure.