Primary Consolidation

Q. Settlement due to creep in soils is contingent on

1. Primary consolidation
2. Scondary consolidation
3. Initial settlement
4. Compaction settlement

Q. Consider the following statements:

1. Consolidation time increases with increasing compressibility.
2. Consolidation time decreases with increasing permeability.
3. Consolidation time is dependent on the magnitude of stress increase.

Which of these statements are correct?

1. 1, 2 and 3
2. 1 and 2 only
3. 2 and 3 only
4. 1 and 3 only

Q. On what factors does the magnitude of primary consolidation depend on
1. Compressibility of soil
2. Magnitude of increase in stress
3. Organic content of soil
4. Permeability of soil

1. 1, 2 and 3
2. 1, 2 and 4
3. 1 and 2 only
4. 3 and 4 only

Q. Reduction in volume of soil primarily due to squeezing out of water from the voids is called

1. primary consolidation
2. Plastic flow
3. creep
4. secondary consolidation

Q. During consolidation process of clayey soils, indicate the sequence of occurrence of the following events in the order from first to last

1. Load being taken up by the pore-water
2. Load being taken up by the soil grains
3. Drainage of water from the pores of the soil

1. 1, 2 and 3
2. 2, 3 and 1
3. 1, 3 and 2
4. 2, 1 and 3

Q. The initial pore water pressure at a point A in a clay layer was 10 kPa. A surcharge of 15 kN/m${}^2$ was placed on Ground surface. The excess pore water pressure at beginning and end of the consolidation of clay layer are (in kN/m${}^2)$

1. 15 and 0
2. 25 and 15
3. 25 and 0
4. 25 and 10

Q. Consider the following statements:

1. The degree of saturation of a saturated soil mass subjected to pressure remains unchanged during the process of consolidation.
2. Secondary consolidation is due to the plastic deformation of the soil when the pore fluid is not subjected to any excess pressure.
3. Primary consolidation is independent of the coefficient of permeability of the soil but depends on the decrease in void volume due to air escape.

Which of these statements are correct?

1. 1 and 2
2. 1 and 3
3. 2 and 3
4. 1, 2 and 3

Q. Directions : Each of the next items consists of two statements, one labelled as the 'Statement (I)' and other as 'Statement (II)'. Examine these two statements carefully and select the answers to these items using the codes given below:

Codes :

Statement (I) : Consolidation is the process of expulsion of pore water by applying steady load for a long time.

Statement (II) : Volume change occurs immediately after the action of the load in case of consolidation tests.

1. Both Statement (I) and Statement (II) are individually true and Statement (II) is the correct explanation of Statement (I)
2. Both Statement (I) and Statement (II) are individually true but Statement (II) is not the correct explanation of Statement (I)
3. Statement (I) is true but Statement (II) is false
4. Statement (I) is false but Statement (II) is true

Q. In soil consolidation process, the following events take place after loading:

1. Decrease in excess pore pressure
2. Increase in total stress.
3. Development of excess pore pressure.
4. Increase in effective stress.

The correct sequence of these events is

1. 3, 2, 1, 4
2. 2, 3, 1, 4
3. 2, 3, 4, 1
4. 3, 2, 4, 1

Q. Consider the following:

1. Initial consolidation
2. Primary consolidation
3. Secondary consolidation
4. Final consolidation

The three stages which would be relevant to consolidation of a soil deposit includes

1. 1, 2 and 3
2. 2, 3 and 4
3. 1, 3 and 4
4. 1, 2 and 4