250+ TOP MCQs on Effect of Water Table on Bearing Capacity and Answers

Geotechnical Engineering Multiple Choice Questions on “Effect of Water Table on Bearing Capacity”.

1. When the water table is above the base of the footing, the submerged weight ‘γ’ can be used to compute __________
a) Effective pressure and Surcharge
b) Pore pressure
c) None of the mentioned
d) All of the mentioned
Answer: a
Clarification: When the water table is above the base of the footing, the submerged weight ‘γ’ should be used for the soil below the water table for computing the effective pressure or the surcharge.

2. Which of the following is an essential difference between Vesic’s and Hansen’s procedure?
a) Different values of Nγ and Variation on some of Hansen inclination
b) Different value of Nq and Nc
c) None of the mentioned
d) All of the mentioned
Answer: a
Clarification: The essential difference in Vesic’s and Hansen’s procedure are i) use of slightly different values of Ny and ii) a variation on some of Hansen’s inclination, base and ground factors.

3. The equation Nc = (Nq – 1) cot φ, have been adopted by ___________
a) Terzaghi and Peck
b) Hansen
c) Vesic
d) All of the mentioned
Answer: d
Clarification: The two equations Nc = (Nq – 1) cot φ and Nq = tan2 (45 + φ/2) ex tan φ have been adopted by i) Terzaghi and Peck ii) Hansen iii) Vesic iv) Meyerhof and Bureau of Indian standards.

4. Which of the following N factors has the widest range of values?
a) Nc
b) Nq
c) Nγ
d) All of the mentioned
Answer: c
Clarification: The Nγ factor has the widest suggested range of any value of N factors. A literature value reveals that for φ = 40°, 38≤ Nγ≤192.

5. Which of the following term does not contribute to q f?
a) Nc
b) Nγ
c) Nq
d) All of the mentioned
Answer: b
Clarification: The Nγ term does not contribute significantly to qf so that almost any reasonable value can be used. Bureau of Indian standards (BIS) recommends using the value of Nγ, given by Vesic.

6. Meyerhof’s extended the analysis of plastic equilibrium of a surface footing to __________
a) Shallow foundation and Deep foundation
b) Inclined foundation
c) None of the mentioned
d) All of the mentioned
Answer: a
Clarification: M Meyerhof’s extended the analysis of plastic equilibrium of a surface footing to Shallow and Deep foundation according to both Terzaghi and Meyerhof analysis.

7. In the Bowl’s method for finding the effect of water table, which of the following factor is used for soil in the wedge zone?
a) Water reduction factor
b) Effective unit weight
c) Overburden pressure
d) Average unit weight
Answer: b
Clarification: In the third method (Bowles, 1988), no water reduction factor is used, but effective unit weight (γe) is used for the soil in the wedge zone.

8. Which of the following equation has been recommended by Indian standard for finding reduction factor in water table?
a) R w = 0.5 (1 + z w2/B)
b) R w = (1 + z w2/B)
c) R w = c Nc + σ̅. Nq + 0.5γBNγ
d) R w = z w2 / B
Answer: a
Clarification: Rw =Rw2 = 5 (1 + z w2 / B) has been recommended by Indian standard at a depth D1 below the ground level.

9. The value of Nc and Nq are same for, which of the following methods?
a) Meyerhof
b) Hansen
c) Vesic
d) All of the mentioned
Answer: d
Clarification: The value of Nc and Nq are same for Meyerhof, Hansen and Vesic method, while subscripts for Nγ identify the author, i.e. N γ(H) = valued by Hansen etc.

10. The factor N γ(M) identifies which of the following author?
a) Vesic
b) Meyerhof
c) Hansen
d) Terzaghi
Answer: b
Clarification: The factor N γ(M) gives values by Meyerhof, as it has the subscript (M) in it.