Civil Engineering Reference
In-Depth Information
Assuming conservatively that
k
1.0 for computing
P
c
2
)(1.35
10
6
)
(
P
c
11.25)
2
731 k
(1.0
12
0
173.5
C
m
0.6
(0.4)
0.6
0.6
ns
0.68
1.0
Use 1.0
66
(0.75)(731)
1
c.
Compute the magnification factor
s
:
Using
k
1.95 as given for determining
P
c
2
)(1.35
10
6
)
(1.95
(
P
c
11.25)
2
192.3 k
12
1
1
1
s
1.84
P
u
0.75
(2)(66)
(0.75)(2
192.3)
1
P
c
d.
Compute the magnified moment:
M
c
(1.0)(173.5)
(1.84)(0)
173.9 ft- k
4.
Consider the loading case U
(
1.2D
1.0L
1.6W
)
as specified in ACI Code Section
9.2.1(b). Analysis results are shown in Figure 11.11.
a.
Are column moments
ACI minimum?
e
min
0.6
0.03
12
0.96 in.
M
2,min
(48)(0.96)
46.08 in.- k
3.84 ft- k
OK
Figure 11.11
