Civil Engineering Reference
In-Depth Information
B
C
A
D
s
P
L
1
Floorbeam reaction at C
FIGURE 5.9
Influence line for floorbeam reaction at location C.
Example 5.3
Determine the maximum bending moment per rail under axle
NP
5ofthe
Cooper's E80 load on a 60 ft long DPG span. The moment at the center, C,
is assumed to be near the maximum bending moment in both location and
magnitude.
The influence line for the center span bending moments is shown in
The ordinates of the influence lines are
=
a
=
(
7
/
30
)
15
=
3.50
b
=
(
15
/
30
)
15
=
7.50
c
=
(
20
/
30
)
15
=
10.00
8′
6′
5′
5′
5′
9′
5′
5′
40 k
40 k
26 k
40 k
26 k
40 k
C
26 k
e
26 k
20 k
d
f
c
g
a
i
b
h
30
′
30
′
A
B
FIGURE E5.3
