Engineering Questions with Answers - Multiple Choice Questions

# Stress Distribution – Equivalent Point Load Method

1 - Question

In Terzaghi’s Theory of one dimensional consolidation, load is applied in _____________
a) one direction only
b) two directions only
c) three directions only
d) none of the direction

Explanation: In Terzaghi’s Theory of one dimensional consolidation, load is applied in one direction only. This direction is usually the vertical direction and the load is applied from the top of the sample.

2 - Question

In Terzaghi’s Theory of one dimensional consolidation, the deformation occurs in __________
a) one direction only
b) two directions only
c) three directions only
d) none of the direction

Explanation: In Terzaghi’s Theory of one dimensional consolidation, load is applied in one direction only. Therefore, the deformation also occurs in one direction only. This direction is usually the vertical direction as the load is applied from the top of the sample.

3 - Question

In Terzaghi’s Theory of one dimensional consolidation, soil is restrained against lateral deformation.
a) True
b) False

Explanation: In Terzaghi’s Theory of one dimensional consolidation, load is applied in one direction only and so the deformation occurs in one direction only. Therefore, as an assumption, the soil is restrained against lateral deformation.

4 - Question

In Terzaghi’s Theory of one dimensional consolidation, excess pore water drains out in __________
a) horizontal direction only
b) tangential direction only
c) vertical direction only
d) both horizontal and vertical direction

Explanation: In Terzaghi’s Theory of one dimensional consolidation, as the load is applied in one direction only, excess pore water drains out in in one direction and that is the vertical direction.

5 - Question

In Terzaghi’s Theory of one dimensional consolidation, the boundary is considered to be __________
a) free surface offering resistance to flow of water
b) free surface offering no resistance to flow of water
c) fixed surface offering resistance to flow of water
d) curved surface offering resistance to water flow

Explanation: In Terzaghi’s Theory of one dimensional consolidation, the boundary is considered to be free surface offering no resistance to flow of water. This is because, when the surface offers resistance to the water flow, it will cause addition pressure to build up. This addition pressure makes the problems complicated to solve.

6 - Question

In Terzaghi’s Theory of one dimensional consolidation, the change in thickness of a layer during consolidation is ___________
a) significant
b) insignificant
c) large
d) very large

Explanation: In Terzaghi’s Theory of one dimensional consolidation, the change in thickness of a layer during consolidation is insignificant. This assumption is because change in thickness is too small to measure.

7 - Question

In Terzaghi’s Theory of one dimensional consolidation, the time lag in consolidation is ___________
a) due to permeability of soil and viscosity of water or fluid
b) due entirely to seepage pressure of water
c) due entirely to permeability of soil
d) due entirely to viscosity of water or fluid

Explanation: The time lag is the delay in consolidation due to slow drainage of water. This entirely depends upon the permeability of the saturated soil and not on the seepage pressure of the water between the soil particles.

8 - Question

In one-dimensional consolidation, secondary consolidation is __________
a) considered at the start of test
b) considered at the middle of test
c) considered at the end of test
d) disregarded

Explanation: Since in Terzaghi’s Theory of one dimensional consolidation, the time lag in consolidation is due entirely to permeability of soil, there is very slow drainage of water that leads to neglecting of the secondary consolidation.

9 - Question

The hydraulic gradient in terms of pore water pressure is given by _________
a) i=γwu¯¯¯hz
b) i=u¯¯¯hγwz
c) i=u¯¯¯hz
d) i=1γwu¯¯¯z

Explanation: The hydraulic gradient i is given by,
i=hzwhereh=u¯¯¯γw
∴ from the two equations, we get,
i=1γwu¯¯¯z.

10 - Question

The rate of change of pore water pressure along the depth of layer represents ____________
a) seepage pressure
b) seepage stress
d) permeability of the soil

Explanation: The hydraulic gradient is the change in total head divided by the distance over which the change occurs. Therefore, the rate of change of pore water pressure along the depth of layer represents the hydraulic gradient.

11 - Question

The velocity with which the excess pore water flows is _________
a) v=k2u¯¯¯z
b) v=1γwu¯¯¯z
c) v=kγwu¯¯¯z
d) v=u¯¯¯z

Explanation: The velocity with which the excess pore water flows is given by Darcy’s law,
v=ki,wherei=1γwu¯¯¯z
Therefore, v=kγwu¯¯¯z.

12 - Question

The rate of change of velocity along the depth of layer is ___________
a) vz=1γw2u¯¯¯z2
b) vz=kγwu¯¯¯z2
c) vz=2u¯¯¯z2
d) vz=kγw2u¯¯¯z2