# If the ratio of the plasticity index and the percentage of clay fraction finer than 2µ is 2, then the soil is classified as:

124 views
in General
closed
If the ratio of the plasticity index and the percentage of clay fraction finer than 2µ is 2, then the soil is classified as:
1. Inactive
2. Normal
3. Active
4. Hyperactive

by (41.6k points)
selected by

Correct Answer - Option 3 : Active

Explanation

The Activity of the soil (A)

The activity of the soil is given by the ratio of the plasticity index (Ip) and the percentage of clay fraction (C) in the soil.

It indicates water absorption capacity or indicates swelling and shrinkage characteristics

${\bf{A}} = \frac{{{{\bf{I}}_{\bf{P}}}}}{{\bf{C}}}$

Where,

C = percentage of clay particles less than a 2-micron size

IP = plasticity index = WL - WP

WL = liquid limit of the soil, WP = plastic limit of the soil

Here, Activity is given as 2 i.e. > 1.25. The soil is active.

 Activity number Type of soil A < 0.75 Inactive A = 0.75 to 1.25 Normal A > 1.25 Active