Foundation Engineering Questions and Answers Part-15

1. The types of slip surface or failure surfaces are ____________
a) 4
b) 2
c) 3
d) 5

Answer: c
Explanation: The types of failure surface are: i) Planar failure surface ii) circular failure surface iii) Non-circular failure surface.

2. The ratio of total depth to depth H is called _________
a) Depth factor
b) Slope depth
c) Depth failure
d) Base failure

Answer: a
Explanation: The ratio of the total depth (H + D) to depth H is called the depth factor Df.

3. The depth factor Df for toe failure is ___________
a) Df > 1
b) Df < 1
c) Df = 1
d) Df = 0

Answer: c
Explanation: For toe failure, Df = 1; for base failure, Df > 1.

4. Planar surface commonly occur in __________
a) Embankment with specific plane of weakness
b) All embankments
c) Soil deposit
d) Foundation of infinite depth

Answer: a
Explanation: Planar failure surface may commonly occur in a soil deposit or embankment with a specific plane of weakness.

5. The stability of a finite slope can be investigated by which of the following method?
a) Bishop’s method
b) Swedish circle method
c) Friction circle method
d) All of the mentioned

Answer: d
Explanation: The stability of a finite slope can be investigated by the following methods:
i) Culmann’s method of planar failure surface
ii) The Swedish circle method
iii) Friction circle method
iv) Bishop’s method.

6. According to Bennet, non-circular slip surface may arise in ___________
a) Non homogeneous dam
b) Embankment dams
c) Homogeneous dam
d) Soil deposit with a specific plane of weakness

Answer: c
Explanation: According to Bennet (1951), non-circular or composite slip surface may arise in homogeneous dam have foundation of infinite depth, rigid boundary planes of maximum and presence of stronger or weaker layer.

7. The rupture mass sliding down a surface in a definite pattern resembles __________
a) Curve
b) Cycloid
c) Ellipse
d) Circle

Answer: b
Explanation: Collin observed that the rupture mass slide down a sliding surface, in a definite pattern resembling that of a cycloid.

8. In stability computation, the curve representing the real surface of sliding is usually replaced by ___________
a) Arc of circle and Logarithmic failure
b) Cycloid
c) None of the mentioned
d) All of the mentioned

Answer: a
Explanation: Failure of finite slopes occurs along a curved surface. In stability computation, the curve is represented by an arc of a circle or logarithmic scale.

9. Rectangular plot method has been suggested by _________
a) Culmann
b) Bishop
c) Singh
d) Terzaghi

Answer: c
Explanation: A simplified rectangular plot method for finding the stability of slopes was suggested by Singh in 1962

10.The slip circle having the minimum factor of safety is called ___________
a) Critical circle
b) Failure slip circle
c) Critical slip circle
d) None of the mentioned

Answer: c
Explanation: A number of trial critical slip circle are chosen against sliding and factor of safety of each is computed. The circle having the minimum factor of safety is the critical slip circle.