Beam Deflection: Unit Load Method Solution

________________________________________________________________________
PROBLEM (12.70) Determine the deflection of point C of the uniformly loaded beam shown in
Fig. P12.70. Use the unit load method.
SOLUTION
w
2
wL
2
wL 2
3 lb
B
1 lb
A
Segment BC: 22()
33
x
L
mx=−−
2
11
22
M
wLx wx=−
2L/3
C
L
/3
Segment AC: 12
3
x
m=
B
A
2L/3
C
L
/3 2
3 lb
312
03
LL
CL
Mm Mm
vdx
EI EI
=+
∫∫
dx
2
3
0
12
()
223
LwLx wx x dx
EI
=−+
∫2
3
0
12
()[
223 3
LwLx wx x L]
x
dx
EI −−+
∫
4
11
927 wL EI
=↓
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