Coefficient of Permeability of Soil by Constant Head Permeameter - Civil Engineering

Saturday, 28 July 2018

Coefficient of Permeability of Soil by Constant Head Permeameter

Coefficient of Permeability of Soil by Constant Head Permeameter 

This test is suitable for coarse-grained soils which are highly permeable.
The apparatus used for this test is called constant head permeameter. Fig (a,b) shows the diagrammatic representation of this test.
Determination of Co-efficient of Permeability by Constant Head Permeameter
Determination of Co-efficient of Permeability by Constant Head Permeameter 
The sample of length 'L' & cross-sectional area 'A' is subjected to a head 'h' which is kept constant (by overflows) during the progress of the test.

The test is performed by allowing the flow of water through the sample and measuring the quantity of discharge (Q) in time 't' with the help of measuring jar. The value of the coefficient of permeability (K) can be computed directly from Darcy's law.

We have from Darcy's law, Discharge per unit time-
(q) = Q/t = K.i.A
or,  K = Q/t.i.A