Question

The maximum shear stress τmax, for a soil mass is equal to ___________

(a) (σ1 – σ3 )/2

(b) (σ1 + σ3 )/2

(c) (σ1×σ3 )/2

(d) (σ3 – σ1 )/2

This question was addressed to me in an interview for internship.

Question is from Mohrs Stress Circle in division Shear Strength of Geotechnical Engineering I

Answer 1

Correct answer is (a) (σ1 – σ3 )/2

To explain I would say: The maximum shear stress τmax is equal to (σ1 – σ3)/2 which occurs on planes with α= 45°.