Correct Answer - Option 3 : 0.4
Explanation:
- The behavior or plasticity of soil depends on the type of mineral (Kaolinite, Illite, Montmorillonite), amount of mineral, and amount of adsorbed water present in the soil.
- Skempton defined a parameter termed as an activity that represents the compressibility or volume change in soil with a change in water content.
- Activity defined as the ratio of plasticity index of soil to the percentage of particles in it having a size less than 2μ (clay size).
The activity of clay,
\({A_t} = \frac{{{I_p}}}{{\% C}}\)
Where,
Ip = plasticity index
%C = % of clay size particle
Mineral
|
Activity
|
Na – Montmorillonite
|
4 - 7
|
Ca – Montmorillonite
|
1.5
|
Na – iIIite
|
0.5 – 1.3
|
Na – Kaolinite
|
0.3 – 0.5
|