Problem $5(25\%)$:

A sandy soil has an internal friction angle ${}^{\text{'}\text{'}-35}.$ In a consolidated$-$drained $($CD$)$ triaxial test. the sandy soil specimen failed at a deviator stress $({}^{\text{'}}-{}^{\text{'}}),$

Part a $(10\%)$: Draw Mohr's cirele at failure condition and include the Mohr$-$Coulomb failure criterion.

Part b $(5\%)$: What is the radius of Mohr's circle at failure?

Part c $(5\%)$: What is the chamber confining pressure, ${}^{\text{'}},(k\frac{N}{m^2})?$

Part $d(5\%)$: What is the major principal stress at failure, ${}_1^{\text{'}}(k\frac{N}{m^2})?$