Geotechnical Engineering Questions and Answers – Friction Circle Method

Geotechnical Engineering Objective Questions

Civil Engineering MCQs

This set of Geotechnical Engineering Multiple Choice Questions & Answers (MCQs) focuses on “Friction Circle Method”.

1. In the friction circle method, it is assumed that the resultant reaction is ___________ to the friction circle.

A) Perpendicular
B) Tangential
C) Parallel
D) None of the mentioned

Answer is C)
Explanation: In the friction circle method, it is assumed that the resultant reaction is tangential in the friction circle, since the error involved in this assumption is of small magnitude.

2. The friction circle may be also referred as __________

A) φ-circle
B) Plane circle
C) Cohesion circle
D) All of the mentioned

Answer is A)
Explanation: The friction circle having radius r sin φ is also called as φ-circle.

3. A circle is considered to be a critical slip circle, if it has ___________

A) Maximum factor of safety
B) Minimum factor of safety
C) Maximum radius
D) All of the mentioned

Answer is B)
Explanation: The circle giving minimum factor of safety Fc is considered as a critical slip circle.

4. The factor of safety with respect to cohesion is given by the equation ____________

A) FC = HC / H
B) FC = C / Cm
C) FC = τf / τ
D) All of the mentioned

Answer is B)
Explanation: The factor of safety Fc with respect to cohesive strength, based on the assumption that the frictional strength has been fully mobilized, is given by FC = C / Cm.

5. The friction circle method assumes the failure surface as ___________

A) Cycloid
B) Curve
C) Arc of circle
D) None of the mentioned

Answer is C)
Explanation: Similar to Culmann’s method, the friction circle method also assumes the failure surface as the arc of circle.

6. The forces acting on a sliding wedge are ___________

A) Weight of the wedge
B) Total frictional force
C) Total cohesive resistance
D) All of the mentioned

Answer is D)
Explanation: The forces acting on a sliding wedge are i) the weight of the wedge ii) the total frictional resistance or resultant, and iii) total cohesive resistance along the slip circle.

7. The factor of safety Fc with respect to cohesive strength is based on the assumption that ___________

A) Frictional force is fully mobilized
B) Frictional force is zero
C) Total cohesive resistance is zero
D) All of the mentioned

Answer is A)
Explanation: The factor of safety with respect to cohesive strength, based on the assumption that frictional force has been fully mobilized, and the equation is given by FC = C / Cm.

8. The factor K, in the radius of the friction circle(Kr sin φ) depends on ____________

A) Radius of the frictional circle
B) Frictional resistances offered
C) Cohesive resistance
D) Central angle of the slip arc

Answer is D)
Explanation: In the frictional circle radius of Kr sin φ, the factor K depends on the central angle δ of the slip arc.