Constant Head Flow
Diameter of sample, D (cm) =
Length of sample, L (cm) =
Area of sample, A (cm^{2}) =
Volume of sample, V (cm^{3}) =
Initial mass of sample, W (g) =
initial water content, w (%) =
Moulding density (g/cm^{3}) =
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 (cm^{3}) 



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 C_{T}
Variable Head Flow
Diameter of standpipe, d (cm) =
Crosssectional area of standpipe, a (cm^{2}) =
Test No. 
1 
2 
3 
Initial head, h_{1 }(cm) 



Final head , h_{2} (cm) 



Time interval in seconds, ( t_{2}  t_{1}) 



Coefficient of permeability (cm/sec), 



Permeability at 27°C = Average of the computed values x C_{T}
