55
Chapter 7
7.1 Eq. (7.1):
s
o
eE
Bq
AAS 21
7.2
2
5.1
2
;53.1
3
6.4
B
H
n
B
L
m
7.3 Eq. (7.4):
fs
s
s
oe II
E
BqS 2
1
)(
Chapter 7
56
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56
m 5.1
2
3
2
B
B
; qo = 180 kN/m2; s = 0.3; = 4
2
2
3
3
2
;53.1
3
6.4
B
H
n
B
L
m
Tables 7.2 and 7.3:
21
21 21
s
s
7.4 Eqs. (7.4) and (7.12):
fs
s
s
oe II
E
BqS 2
1
)(93.0
Chapter 7
57
7.5 Eqs. (7.4) and (7.12):
fs
s
s
oe II
E
BqS 2
1
)(93.0
12
1.2
1.2
000,16
e
7.6 From Eq. (7.14) the equivalent diameter,
Chapter 7
58
© 2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part.
58
788.0
56.1
)23.0)(2(
)500(
2
56.1
9000
1015
1064
1
4
2
2
1064
1
4
3
6
3
.
π
Bt
k
B
E
E
.
π
I
e
e
o
f
F
Eq. (7.19):
917.0
61
1
56.1
]40)4.0)(221(exp[53
1
1
61)40221(exp53
1
1
....
.
D
B
...
I
f
e
s
E
Eq. (7.17):
 
mm 13.6
m 0.0136
)4.01(
9000
)917.0)(788.0)(68.0)(56.1)(190(
122
s
o
EFGeo
eE
IIIBq
S
7.7 Eq. (7.17):
 
2
1s
o
EFGeo
eE
IIIBq
S
qo = 150 kN/m2
)385.3)(400(
e
kB
Chapter 7
59
© 2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part.
91.5
385.3
20
e
B
H
From Figure 7.6, IG 0.89. From Eq. (7.18):
815.0
385.3
)25.0)(2(
)400(
2
385.3
000,16
1015
1064
1
4
2
2
1064
1
4
3
6
3
.
π
B
t
k
B
E
E
.
π
I
e
e
o
f
F
From Eq. (7.19):
923.0
61
5.1
385.3
]40)3.0)(221(exp[53
1
1
61)40221(exp53
1
1
....
.
D
B
...
I
f
e
s
E
mm 19.3 m 0.0193
000,16
3.01
)923.0)(815.0)(89.0)(385.3)(150(2
e
S
7.8 Eq. (7.22): At z = 0:
)1(
)( 1.05.0
z
mz q
Chapter 7
60
60
lb/in. 20.83
144
2
3000 qqqo
Depth (ft)
z (in.)
Es (lb/in.2)
Iz
)( z
E
I
s
z
0 – z1 = 0 – 3.31
39.72
3200
409.0
2
71.0107.0
0.00508
z1 – z2 = 3.31 – 13.31
120
3200
355.0
2
071.0
0.01331
∑0.01839
Eq. (7.20):
)()(
21 z
E
I
qqCCS
s
z
e
q = Df = (115)(2.5) = 287.5 lb/ft2 = 1.997 lb/in.2
2
lb/in. 20.83
144
3000 qqqo
1 ;952.0
83.20
997.1
5.015.01 21
C
qq
q
C
Se = (0.952)(1)(20.83)(0.01839) = 0.365 in.
61
7.9
Iz = 0.2
@ z = 0
Iz = 0.6
@
ft 3.125
2
25.6
2B
z
Iz = 0
@
ft 15.05
25.6
10
log1)25.6)(2(log12
2
B
L
Bz
Depth (ft)
z (in.)
Es (lb/in.2)
Iz
)( z
E
I
s
z
0 – z1 = 0 – 3.125
37.5
3200
3.0
2
6.00
0.003516
z1 – z2 = 3.125 – 15.05
143.1
3200
3.0
2
06.0
0.01342
∑0.016936
Eq. (7.29):
)()( 2
0z
E
I
qqCS z
s
z
de
4.0
25.6
5.2
B
Df
; Cd 0.89 (Table 7.6)
in. 0.314)016936.0)(83.20)(89.0(
e
S
7.10 Eq. (7.21):
)1(
)( 1.05.0
z
mz q
qq
I
Chapter 7
62
62
Depth (m)
z (m)
Es (kN/m2)
Average Iz
)( z
E
I
s
z
0 – 2
2 – 2.5
2.5 – 8
8 – 10
2.0
0.5
5.5
2.0
6,125
12,075
12,075
10,150
0.3812
0.6077
0.4135
0.087
0.000124
0.000025
0.000188
0.000017
∑0.000354
7.11 The strain influence diagram is shown on the following page.
Also, Es = 1.4Esquare = (1.4)(3.5qc) = 4.9qc
Chapter 7
63
Depth (m)
z (m)
Es (kN/m2)
Iz
)( z
E
I
s
z
0 – 1.25
1.25 – 2
2 – 8
8 – 10
1.2
0.75
6
2
8,575
8,575
16,905
14,210
0.4
0.5745
0.343
0.0685
0.000056
0.00005025
0.0001217
0.00000964
∑0.0002376
0
E
s
de
Post construction settlement:
Chapter 7
2
2
MN/m3
10
)2)(9.2()6)(45.3()2)(75.1()(
z
zqc
Settlement
mm 23.7 m 0237.0
1
10365
log)10(
3
1.0
)02.0(
Total settlement = 33.5 + 23.7 = 57.2 mm
7.12
Depth (ft)
N60
5
10
15
20
25
10
12
9
14
16
Average N60 = 12
From Eq. (7.35): Allowable
ed SF
B
B
N
q2
60
net 1
4
B = 5 ft; Se = 1 in.
198.1
5
3
)33.0(133.01
B
D
Ff
d
2
kip/ft 5.18
)1)(198.1(
5
15
4
12 2
net
q
7.13 Eq. (7.44):
75.0
4.1
RR B
B
B
z
aRR
B
B
L
B
321 25.0
65
Normally consolidated sand:
053.0
)12(
71.1
)(
71.1
;14.0 4.14.1
60
21 N
7.14 B = 5 ft; L = 10 ft; d = 5 ft; e = 0.5 ft
Chapter 7
66
66
o
R
R
pp(m)
(lb/in.2)
1
B
Se
Se 2
(in.)
3
qo 4
(lb/in.2)
Qo 5
(kip)
0.002
0.004
0.008
0.012
0.024
0.05
0.08
0.10
0.20
7.2
24.2
32.6
42.4
68.9
126.1
177.65
210.5
369.6
0.00048
0.00096
0.00192
0.00288
0.00576
0.012
0.0192
0.024
0.048
0.0288
0.0576
0.1152
0.1728
0.3456
0.72
1.152
1.44
2.88
2.27
2.17
2.0
1.86
1.7
1.35
1.1
1.07
0.9
10.92
35.08
43.55
52.68
78.24
113.72
130.54
150.46
222.2
78.62
252.58
313.56
379.3
563.33
818.78
939.89
1083.31
1599.84
)24.0(
1
o
eR
R
B
S
in. )60()(
2
B
S
B
B
S
See
e
3 Figure 7.16
ompmp qppf )()(
4 668.0
1000
.)in 120.in 60)(lb/in. (
(kip) 2
5
o
oo q
BLqQ
The plot of Se versus Qo is shown. From the plot, Qo at 1 in. settlement is 900 kip.
Chapter 7
67
)4.62120(
10
)4.62122)(3()100)(5.4(15.7
o
8.916
7.1
1av
)( o
o
pe e
Chapter 7
68
68