Environmental Engineering Reference
In-Depth Information
8.0
a. e
o
= 7.6, Right hand scale
P
o
a.
7.6
P
c
Left hand
scale
3.0
7.0
P
o
2.8
b.
P
c
2.6
6.0
2.4
2.2
5.0
2.0
1.8
4.0
c.
P
o
P
c
1.6
1.4
3.0
d.
P
o
P
c
e.
1.2
f.
g.
P
o
P
c
P
c
≈
P
o
c.
2.0
1.0
d.
P
o
h.
i.
P
o
P
c
(i)
P
c
(h)
0.8
f.
l.
0.6
g.
i.
e.
h.
0.4
0.1
0.2
0.3 0.4
0.6 0.81.0
Pressure (kg/cm
2)
2
3
4 5 6 7 8910
20
30
Material
d
w
LL
PI
Material
d
w
LL
PI
a
. Soft silty clay
(lacustrine, Mexico)
b
. Soft organic silty clay
(alluvium, Brazil)
c
. Soft organic silty clay
(backswamp, Georgia)
d
. Stiff clay varve
(glaciolacustrine,
New York)
e
. "Porous" clay
(residual, Brazil)
0.29
0.70
300
92
410
260
f
. Medium sandy, silty clay
(residual gneiss, Brazil)
g
. Soft silty clay
(alluvium, Texas)
h
. Clayey silt, some fine
sand (shallow alluvium,
Georgia)
i
. Stiff clay
(Beaumont clay, Texas)
j
. Silt varve (glaciolacustrine,
New York)
1.29
38
32
40
48
16
33
0.96
65
46
76
62
31
34
1.46
29
53
24
1.39
29
81
55
1.05
32
43
16
FIGURE 3.81
Typical pressure-void ratio curves for various clay soils.
Origin for compression
Undisturbed sample
0.5d
Disturbed sample
1.0 d
Primary
consolidation
for load
∆
p
Initial
height
2H
50
Primary consolidation
100
0.197H
2
50
C
v
=
1.0 d
Secondary compression
(2H)
C
α
100
Log of 1 cycle = 1
1
2
3
5
7
10
20 30
Time (log scale) (min)
50
70
100
200
300
500
700
1000
FIGURE 3.82
Compression vs. time for one load cycle.
