### Three Phase Diagram of Soil EXPLANATION

Soil Mass is the complex mixture of mainly three Particle called Water, Air, Solid. the first two particles generally fill in a porous structure. Which is formed due to space creation between solid particle. For a better understanding of particle arrangement, we see each particle separately in form of Diagram. this separation of solid, air, water called three phase diagram system of soil. now Question is What its use in soil. and the answer, it helps to find one of the most important Relations in soil engineering. so today we talk about volumetric type relation (Void ratio, porosity of soil, degree of saturation, percentage air voids, air content). with three phase diagram of soil

fig show actual soil mass and soil in form of a three phase diagram

For easy understanding, we write volume part on left and mass part on the right of the diagram.

When weight considers instant of mass, its written on the right side.

Vv =volume of voids
Va= volume of air
Vw= volume of water
Vs= volume of solid
V= total volume

Ma = 0 mass of air is very low so we neglect it.
Mw= mass of water, Ms = mass of solid, M= total mass

### Two-phase diagram of soil

above we see soil consist of three particles, but it may be two particles in some case,

firstly say our soil mass consist of only Water and solid, that happens when the soil is fully saturated.

let's say a soil mass consists of all three particles. Then we start adding water until its fully submerged,
now the air is gone and only two things remaining are Water and Solid

Its maybe only solid or air particle possibility in soil mass. that happens when you completely dry the soil mass,

so water evaporates and only solid and air remains.  as shown in fig

That's all about three phase system of soil, now we talk about volumetric relation ex - What is the void ratio, Porosity, Degree of saturation and air voids