By using the Terzaghi’s theory the rate of consolidation can be determined. The assumptions are:
The compression and flow are 1-D only (in the vertical direction only)
The soil is homogeneous
The soil is completely saturated
Dercy’s law is valid
Both water inside the pore and soil grains are incompressible
Strains are small
Void ratio decreases with the increase in applied stress. Hence change in void ratio, de = -av \[d\bar \sigma\] , where av is the coefficient of compressibility.