Constant Head Flow
Diameter of sample, D (cm) =
Length of sample, L (cm) =
Area of sample, A (cm2) =
Volume of sample, V (cm3) =
Initial mass of sample, W (g) =
initial water content, w (%) =
Moulding density (g/cm3) =
Head loss, h
(cm) =
Hydraulic gradient, i = h / L =
Temperature of water, T (°C) =
Test No. |
1 |
2 |
3 |
| Time interval, t (sec) | |||
Quantity of flow, Q (cm3) |
|||
Coefficient of permeability (cm/sec), |
Correction factor due to temperature, 
where
h is viscosity of water.
Permeability at 27°C = Average of the computed values x CT
Variable Head Flow
Diameter of standpipe, d (cm) =
Cross-sectional area of standpipe, a (cm2) =
Test No. |
1 |
2 |
3 |
| Initial head, h1 (cm) | |||
| Final head , h2 (cm) | |||
| Time interval in seconds, ( t2 - t1) | |||
Coefficient of permeability (cm/sec), |
Permeability at 27°C = Average of the computed values x CT