GATE Exam Questions - Engineering

Q1:

A deep cut of 7 m has to be made in a clay with unit weight 16 kN/m3 and a cohesion of 25 kN/m2. What will be the factor of safety if one has to have a slope angle of 30° ? Stability number is given to be 0.178 (from Taylor's chart) for a depth factor of 3.

A 0.80

B 1.1

C 1.25

D 1.0

ANS:C - 1.25

FOS = Cu/(γ*Ns*h).
= 25/(16*0.178*7).
= 1.25.