THE COOPER UNION Albert Nerken School of Engineering Soil Mechanics Laboratory Experiment No. 6 - Constant Head Permeability Test
 Name: Date: Group No.: Members:

 Location: Depth: Horizon: Boring: Elevation: Agronomic Name: Geological Region: Sample: Description:

Formulae:

1) kT = ql/hAt             2) k20 = kT(5T/520)(g20/gt)             3) Dr = ((1/gd min - 1/gd nat)/(1/gd min - 1/gd max))*100%

 kT = coefficient of permeability, cm/s, as observed temperature k20 = coefficient of permeability corrected to 20:C mT = absolute viscosity of liquid at T C, in g-s/cm2 m20 = absolute viscosity of liquid at 20:C, in g-s/cm2 q = quantity of water collected, in cc L = distance the head loss h occurs in, or distance between h = head loss, in cm piezometer outlets, in cm A = cross-sectional area of sample, in cm2 Dr = relative density, in % gd max = maximum dry unit weight, in pcf gd min = minimum dry unit weight, in pcf gd nat = natural, or compacted dry unit weight, in pcf g20 = unit weight of liquid at 20:C, in g/cm3 gt = unit weight of liquid at T:C, in g/cm3 t = time to collect the water, q, in sec

Table 1 [Data Sheet (A)]: Sample Preparation Data

 Determination Number: 1 2 3 Area of Sample, A (cm2): Length of Sample, L' (cm): Distance Between Piezometers, L (cm): Total Volume of Sample, Vt (cc): Weight of Container & Soil Before (g): Weight of Container & Soil After (g): Weight of Dry Soil Sample (g): Specific Gravity, Gs: Dry Unit Weight of Sample (pcf): Max. Dry Unit Weight of Soil (pcf): Min. Dry Unit Weight of Soil (pcf): Relative Density, Dr (%): Void Ratio of Sample, e: Porosity of Sample, n (%):

Table 2 [Data Sheet (B)]: Run Data

 Determination Number: Run Number Piezometer Readings Loss in Head, h (cm) Hydraulic Gradient, i = h/L Time, t (sec) Quantity, q (cm3) Temperature, T (:C) V=q/At @ T, :C (cm/sec) V=q/At @ 20 :C (cm/sec) h1 (cm) h2 (cm) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15