As per Rankine's theory of earth pressure, the inclination of failure planes is $\left ( 45 + \frac{\phi }{2} \right )^{\circ}$ with respect to the direction of the minor principal stress.
The above statement is correct for which one of the following options?
- Only the active state and not the passive state
- Only the passive state and not the active state
- Both active as well as passive states
- Neither active nor passive state