Plasticity Of Soil
Plasticity is the ability of soil to undergo deformation without cracking or fracturing. Actually, plasticity is the main index property of fine-grained soil, especially clayey soil. When the soil has plasticity then it can be moulded into various shapes when it is wet.
Do you know the plasticity in the soil is basically due to the presence of clay minerals? Let me explain it, the clay mineral particles carry a negative charge on their surfaces, and water molecules are attracted toward the clay mineral surface, this phenomenon is known as adsorbed water.
The clay particles are separated by the adsorbed water layer which allows the clay particles to take any shape when the clay particles are subjected to deformation.
When the water content in the soil decreases the plasticity of the soil also reduces.
Why Is the Plasticity Of Soil Important?
If soil does not possess the plasticity property in it then it is very difficult to change the shape of the soil when it is wet, that is why the plasticity of soil is very important.
Why Adsorbed Water Is Necessary In Soil For The Plasticity Of Soil?
To impart the characteristics of plasticity the adsorbed water is very necessary, actually, it helps the soil to change different shapes. In the clay, the adsorbed water exists in the form of layers and helps the clay to change its shape.
Here one point is to notice that when the soil is mixed with a non-polarizing liquid, such as kerosene oil, the soil does not impart the plasticity characteristics in it (Note- water is a polarizing liquid). Actually, the non-polarizing liquid does not have electromagnetic properties to react with clay minerals.
Does Clay Minerals Are Important For The Plasticity Characteristics Of Clay?
For the plasticity characteristic of the soil, the clay minerals as well as the adsorbed water are very necessary. If there is a non-clay mineral, such as quartz, then the soil would not become plastic.