Environmental Engineering Reference
In-Depth Information
TABLE 3.12
Typical Permeability Coefficients for Rock and Soil Formations
a
k
(cm/s)
Intact Rock
Porosity
n
(%)
Fractured Rock
Soil
Practically
10
10
Massive
0.1-0.5
Homogeneous clay
impermeable
10
9
low-porosity
0.5-5.0
below
10
8
rocks
zone of weathering
10
7
Low discharge,
10
6
5.0-30.0
Very fine sands,
poordrainage
10
5
Weathered
organic and
10
4
granite Schist
inorganic silts,
10
3
Clay-filled joints
mixtures of sand
and clay, glacial
till stratified clay
deposits
High discharge,
10
2
Jointed rock
Clean sand, clean
free draining
10
1
Open-jointed rock
sand and
1.0
Heavily
gravel mixtures
10
1
fractured rock
Clean gravel
10
2
a
After Hoek, E. and Bray, J.W.,
Rock Slope Engineering,
Institute of Mining and Metallurgy, London, 1977.
TABLE 3.13
Permeability Coefficients for Some Natural Soil Formations
a
Formation
Value of
k
(cm/s)
River Deposits
Rhone at Genissiat
Up-0.40
Small streams, eastern Alps
0.02-0.16
Missouri
0.02-0.20
Mississippi
0.02-0.12
Glacial Deposits
Outwash plains
0.05-2.00
Esker, Westfield, Mass.
0.01-0.13
Delta, Chicopee. Mass.
0.0001-0.015
Till
Less than 0.0001
Wind Deposits
Dune sand
0.1-0.3
Loess
0.001
Loess loam
0.0001
Lacustrine and Marine Offshore Deposits
Very fine uniform sand,
C
u
5 to 2
b
0.0001-0.0064
Bull's liver, Sixth Ave, N.Y.,
C
u
5 to 2
0.0001-0.0050
Bull's Liver, Brooklyn,
C
u
5
0.00001-0.0001
Clay
Less than 0.0000001
a
From Terzaghi, K. and Peck, R.B.,
Soil Mechanics in Engineering Practice,
2nd ed., Wiley, New York, 1967. Reprinted with permission of John Wiley
& Sons, Inc.
b
C
u
uniformity coefficient.
