Engineering Questions with Answers - Multiple Choice Questions

# Determination of Coefficient of Permeability

1 - Question

Permeability can be determined by direct measurement with the help of ___________
a) Permeameter
b) Consolidation test
c) Horizontal capillary test
d) Pumping-out test
Explanation: Permeability of soil can be determined by permeameters, by allowing the water to flow through soil sample under either constant head or under variable head.

2 - Question

Which of the following formula, cannot be used for determining the permeability of soil?
a) Jacky’s formula
b) Allen Hazen’s formula
c) Kozney’s formula
d) Darcy’s formula
Explanation: In Darcy’s equation or Darcy’s law, there is no permeability constant. q = k i A Hence it cannot be used for finding permeability of soil.

3 - Question

Coefficient of permeability of soil can be determined by which of the following method?
a) Laboratory methods
b) Field methods
c) Indirect methods
d) All of the mentioned
Explanation: The coefficient of permeability can be determined by the following methods: i. Laboratory method – constant head permeability and falling head permeability test ii. Field method –pumping-out and pumping-in test iii. Indirect methods- horizontal capillary test and consolidation test data.

4 - Question

Allen Hazen’s formula is given by which of the following equations?
a) K = 100m2
b) K = C D102
c) K = 200De2e2
d) None of the mentioned
Explanation: Allen Hazen’s formula is K=CD102, where c is constant, which is taken as approximately equal to 100 when D10 is expressed in cm.

5 - Question

The unit of coefficient of absolute permeability(K) is ____________
a) Kg/cm
b) m/s2
c) m2
d) All of the mentioned
Explanation: Since K has the dimension of area (i.e. [k] = [L2]), the unit of K is m2.

6 - Question

Coefficient of absolute permeability (K) depends on ____________
a) Permeant
b) Properties of soil mass
c) Degree of saturation
d) All of the mentioned
Explanation: From the equation of coefficient of absolute permeability, K = C (e3/1+e) D3 We can find that coefficient of permeability is independent of the properties of permeant (i.e. water) and it depends solely on the properties of soil mass.

7 - Question

In Terzaghi’s formula K = 200De2e2, De2 represents ____________
a) Effective grain shape
b) Void ratio
c) Effective grain size
d) Permeability
Explanation: De=effective grain size, the diameter of the sphere for which the ratio of its volume to its surface area is the same as the similar ratio for a given assemblage of soil particles.

8 - Question

K = 100Dm2, is given by which of the following formula?
a) Terzaghi’s formula
b) Kozney’s formula
c) Jacky’s formula
d) Allen Hazen’s formula
Explanation: In 1944, Jacky found out the order of magnitude of k can be obtained from all soils from the formula K= 100Dm2, where Dm denotes grain size.

9 - Question

Terzhagi’s formula can be applied for_________
a) Uniform sand
b) Clay soil
c) Coarse-grained soil
d) Fine-grained soil