Civil Engineering Reference
In-Depth Information
33,600 tan 23
740
__________________
FS
7330
2.05
For overturning analysis: Taking moments about the toe of the wall gives
7330
20
P
A
H
__
___
Overturning moment
3
3
48,900
Moment of weight
33,600
14
___
2
235,000
FS
235,000
_______
48,900
4.81
Solution: Earthquake Analysis.
Using Eq. (10.7), we get
P
E
1
2
k
A
1
2
(
a
max
g
) (
H
2
t
)
1
2
(0.333)
1
2
(0.20)(20)
2
(110)
2540 lb
ft
For sliding analysis, use Eq. (10.13):
FS
N
tan
P
p
33,600 tan 23
740
___________
P
H
P
E
__________________
2540
1.52
7330
For overturning analysis, use Eq. (10.14) with
P
v
0.
33,600(7)
Wa
______________
_________________________
FS
3
HP
E
3
(20)(2540)
2.84
1
3
P
H
H
2
1
3
(7330)(20)
2
In summary,
Static conditions:
FS sliding
2.05
FS overturning
4.81
Earthquake conditions (
a
max
0.20
g
):
FS sliding
1.52
FS overturning
2.84
10.3 RETAINING WALL ANALYSES FOR
LIQUEFIED SOIL
10.3.1 Introduction
Retaining walls are commonly used for port and wharf facilities, which are often located in
areas susceptible to liquefaction. Many of these facilities have been damaged by earthquake-
induced liquefaction. The ports and wharves often contain major retaining structures, such
