# PARAM VISIONS

All about civil construction knowledge- PARAM VISIONS

### What is a void ratio of soil? - Significance & formula of void ratio.

1. What is a void ratio?

The void ratio of soil is the ratio of the volume of voids to the volume of solids.

Let us observe the 3-phase diagram of the soil as below.

We can write the void ratio as

e = [Vv / Vs]

From the above diagram, we can also say

e = [ Vv / (V - Vv)]

Where,

V = total volume.

Vv = volume of voids.

Vs = volume of solid.

Va = volume of air.

Vw = volume of water.

2. What is the unit & symbol of void ratio?

The void ratio is represented by the symbol  ðŸ‘‰ e.

As it is the ratio of the two different volumes, it does not have any unit.

3. What is the importance of the void ratio in soil?

The soil is a mixture of different size particles. These distributed particles are varied in their characteristics & properties.

So, the void ratio becomes an important factor to determine the soil properties like permeability, shear strength, density, compressibility, porosity, etc. All these properties are closely related to the void ratio of that particular soil.

Therefore, the void ratio is considered more significant than the porosity.

4. Can the void ratio be zero in soil?

No. The volume of voids cannot be zero in the case of soil.

So, in all circumstances, void ratio (e ) > 0.

Thank you for going through this article. Have a good day ðŸ˜„.