Compressibility Parameters

Q. Compression index developed by Casagrande is

1. $C_V=0.009(LL+10\%)$
2. $C_V=0.009(LL-10\%)$
3. $C_V=0.009(LL+10\%)$
4. $C_V=0.0009(LL+10\%)$

Q. Match List-I (Term) with List-II (Definition) and select the correct answer using the codes given below the lists (where 'e' is void ratio, 'p' is effective vertical stress 'k' is permeability and ${\gamma }_w$ is unit weight of water):

List-I
A. Compression index, $C_c$
B. Coefficient of volume change, $m_v$
C. Coefficient of compressibility, $a_v$
D. Coefficient of consolidation, $C_v$

List-II

1. Slope of the e-p curve defined as $\Delta e/\Delta p(1+e_0)$
2. Slope of e-long p curve given by $[-\Delta e/\Delta logp]$
3. $\text{Term defined as}k/\left(m_v{\gamma }_w\right)$
4. Slope of the e-p curve defined as $-\Delta e/\Delta p$

Codes :

A B C D

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

Q. The virgin compression curve for a soil is shown in figure below. What is the compression index of the soil?

1. 0.3
2. 0.5
3. 1.5
4. 15

Q. Consolidation test was conducted on two soils A and B respectively. The soil A is 1.5 times more compressible than soil B. The thickness of A was 2 times that of B. If the time required for 50% consolidation was three times longer for soil A than for soil B, the ratio of coefficient of permeability of A to that of B is ?

1. $0.5$
2. $1$
3. $2$
4. $4$

Q. Consider the following statements:

1. Immediate settlement takes place as soon as the load is placed.
2. Secondary settlement is significant in the case of organic soil.
3. Secondary settlement is estimated based on the 'void ratio versus time curve' for a particular load under consolidation test.

Which of the above statements are correct?

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

Q. If, instead of single drainage, the number of drainage faces is increased to two in responding soils, the rate of compression will be

1. 4 times slower
2. 2 times slower
3. 4 times faster
4. 2 times faster

Q.
The virgin compression curve with axes adopted as per convention in this regard for a clay soil is shown in the figure. The compression index of the soil is

1. 0.25
2. 0.50
3. 1.00
4. 1.25

Q. In a consolidation test void ratio decreased from 0.80 to 0.70 when the load was changed from $40kN/m^{2}to80kN/m^2$. What is the compression index?

1. 0.14
2. 0.16
3. 0.33
4. 0.66

Q. The slope of the e-log $\sigma$ curve for a soil mass gives

1. coefficient of permeability, k
2. coefficient of consolidation $C_v$
3. compression index, $C_c$
4. coefficient of volume compressibility, $m_v$

Q. When a structural load is applied on a soil stratum, which of the following soil types will have the minimum settlement?

1. Over-consolidated clay stratum
2. Clayey silt stratum
3. Normally consolidated clay stratum
4. Sandy clay stratum