Environmental Engineering Reference
In-Depth Information
60
Measured data (drying)
Measured data (wetting)
Fitted curve
50
RS (W)
40
RS (D)
30
MRF_60-40 (D)
20
GS (D)
MRF_60-40 (W)
10
GS (W)
0
10
6
0.01
0.1
1
10
100
1000
10,000
100,000
Matric suction (
u
a
-
u
w
), kPa
Figure 7.36
Independently Measured SWCCs for Soils in NTU Water Flow study Krisdani
et al. (2009).
Table 7.7 Basic Properties of Soils in NTU Study
Soil
No.
Description
RS
MRF 60-40
GS
1
Unified Soil Classification System
(ASTM, 2006)
Sandy silt (ML)
Silty sand (SM)
Gravelly sand (SP)
2
Specific gravity,
G
s
2.65
2.65
2.62
3
Grain-size analysis
Gravel content (
>
4.75 mm) (%)
0.6
0.1
49.9
Sand content (0.075-4.75 mm) (%)
32.1
59.1
50.1
Fine content (
<
0.075 mm) (%)
67.3
40.8
0.0
4
Atterberg limits
Liquid limit, LL (%)
47.0
34
—
Plastic limit, PL (%)
32.0
22
—
Plasticity index, PI (%)
15.0
12
—
10
−
8
10
−
7
10
−
2
5
Saturated coefficient of permeability,
k
s
(m/s)
a
8
.
6
×
2
.
7
×
7
.
6
×
Source:
After Krisdani et al., (2009)
a
Obtained from falling-head tests.
of the SWCCs are listed in Table 7.8. The basic properties
and SWCC of the gravelly sand were measured by Krisdani
et al. (2009).
A large-scale model slope was set up and filled with the
above-mentioned soils. The model was used to study the
infiltration and evaporation of water from the slope. The
infiltration box was fabricated using stainless steel frames
and acrylic sheets as the sidewalls. The size of the infiltration
box was 2.45m in length, 2.0m in height, and 0.4m in
width. A number of holes were drilled along the sidewalls
for the installation of measuring devices. Some additional
holes were provided for collection of runoff. Drainage was
also provided at the front panel of the infiltration box. A
PVC (polyvinyl chloride) plate was installed as the base of
the slope model to form an impervious boundary condition
during the experiments.
The measuring devices consisted of tensiometers for the
measurement of negative pore-water pressures and time
domain reflectometry (TDR) for the measurement of vol-
umetric water content.
In addition, weighing balances
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