Environmental Engineering Reference
In-Depth Information
75
75
70
70
65
65
60
60
a
f
= 10,
n
f
= 2,
m
f
= 1
k
sat
= 10
−
55
1
m/s
55
50
a
f
= 10,
n
f
= 1,
m
f
= 1
−
160
−
120
−
80
−
40
0
40
50
Pore-water pressure (kPa)
−
160
−
120
−
80
−
40
0
40
(a)
Pore-water pressure (kPa)
75
(a)
70
75
65
70
60
65
a
f
= 10,
n
f
= 2,
m
f
= 1
k
sat
= 10
−
55
1
m/s
60
50
55
−
160
−
120
0
−
80
−
40
40
a
f
= 10,
n
f
= 2,
m
f
= 1
Pore-water pressure (kPa)
50
(b)
160
120
80
0
40
−
−
−
−
40
75
Pore-water pressure (kPa)
70
(b)
65
75
60
70
a
f
= 10,
n
f
= 2,
m
f
= 1
k
sat
= 10
−
55
1
m/s
65
50
−
160
−
120
60
−
80
−
40
0
40
Pore-water pressure (kPa)
(c)
55
a
f
= 10,
n
f
= 3,
m
f
= 1
0.001
0.01
0.2
Hydrostatic
50
50
q/k
sat
0.1
160
Pore-water pressure (kPa)
(c)
120
80
0
40
−
−
−
−
40
0.5
Figure 8.80
Comparison of pore-water pressure profiles for
soils with varying saturated coefficients of permeability
k
sat
:(a)
k
sat
=
10
−
3
m/s, (b)
k
sat
=
10
−
5
m/s, and (c)
k
sat
=
10
−
7
m/s (after
Zhang et al., 2004).
0.001
0.1
0.5
0.01
0.2
Hydrostatic
q
/
k
sat
Figure 8.84 presents the SWCCs and the corresponding
permeability functions for soils with varying
n
f
values. The
theoretical long-term matric suction along the vertical por-
tion of the pore-water pressure profiles for soils with varying
n
f
values does not decrease or increase monotonically by a
significant amount as
n
f
varies with a constant
q/k
sat
ratio.
These results assist in explaining the pore-water pressure
profiles shown in Fig. 8.81.
Figure 8.81
Comparison of pore-water pressure profiles for soils
with various
n
values: (a)
n
f
=
1, (b)
n
f
=
2, and (c)
n
f
=
3
(after Zhang et al., 2004).
conditions on the pore-water pressure profiles can be
illustrated by starting from a hydrostatic condition. It should
be noted that varying initial soil moisture conditions can
significantly influence rainfall infiltration and pore-water
pressure profiles in a slope (Freeze, 1969; Tsaparas et al.,
2002).
8.4.3 Numerical Modeling of Transient Conditions
The effects of air-entry value, water storage capacity, satu-
rated coefficient of permeability, and groundwater boundary
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