According to Terzaghi's bearing capacity theory, the angle of shear failure planes of the Rankines passive zones of linear shear, with the horizontal is _____________. (where φ = angle of internal friction)

Question

Question

This question was previously asked in

RRB JE CE 22 Apr 2025 Shift 2 CBT 2 Official Paper

Answer 1

Explanation:

In Terzaghi’s bearing capacity theory, two Rankine zones are formed:

Additional Information

In passive failure, the major principal stress is vertical, and the minor principal stress is horizontal.

In Mohr-Coulomb theory:

The angle between the failure plane and the direction of major principal stress is:
$\theta = 45^\circ + \frac{\phi}{2}$

But this angle is with respect to the major principal plane, which is vertical in passive zones.

So, the angle with the horizontal is:

$90^{\circ} - (45^{\circ} + \frac{ϕ}{2}) = 45^{\circ} - \frac{ϕ}{2}$