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PROBLEM (10.108 through 10.111) A cantilever beam is loaded as shown in Figs. P10.108
through P10.111.Determine:
(a) The slope at the free end.
(b) The deflection at the free end.
SOLUTION (10.108)
We have θ A = 0 and v A = 0 .
y
MA =
2 2
wL
9
w
A 2L/3
2
RA = wL
3
M
A
EI
2
− wL2
9
C
B
L/3
C
B
x
Parabolic
Spandrel
x
Tangent at A
A
C
vB
θB
3
3 2L L
x = b=
=
4
4 3
2
1 bh
1 1 2L 2 2
4wL3
A=−
=−
wL = −
EI 3
EI 3 3 9
81EI
(a) Equation (10.48) becomes
θ B A = θ B − 0 = A , or
θB =
4wL3
81EI
(b) Equation (10.50):
vB = t B A
L
4wL3 5 L
10 wL4
= − A( x + ) = −
( )=
↓
3
81EI 6
243 EI
Continued on next slide
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instructional purposes only to students enrolled in courses for which the textbook has been adopted. Any other
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SOLUTION (10.109)
P
2P
C
A L/2
M
EI
L/2
B
x1
x
A1
-PL
M
EI
x2
A2
x
C
-PL
Tangent at A
A
tB/A
tC/A
(a) θ B = θ B / A = A1 + A2 = −
(b) vB = t BA
θA = 0
vA = 0
1 PL2 1 PL2 3 PL2
−
=
2 EI 4 EI
4 EI
PL2 2 L PL2 5 L
13 PL3
( )−
( )=
= A1 x1 + A2 x2 = −
↓
2 EI 3
4 EI 6
24 EI
SOLUTION (10.110)
w0
A
L
B
w0L2/6
w0L2/6
x
Cubic
spandrel
M
EI
A
w0 L2
−
6
Tangent at A
B
tAB
x=
n +1
4
b= L
5
n+2
vB = 0
θB = 0
A
w0 L2
w0 L3
1
bh
( L)(
)=−
A=
=
4 EI 4 EI
6
24 EI
Continued on next slide
Excerpts from this work may be reproduced by instructors for distribution on a not-for-profit basis for testing or
instructional purposes only to students enrolled in courses for which the textbook has been adopted. Any other
reproduction or translation of this work beyond that permitted by Sections 107 or 108 of the 1976 United States
Copyright Act without the permission of the copyright owner is unlawful.
w0 L3
θA =
(a) θ B / A = θ B − θ A = A ,
24 EI
3
w L 4L
w L4
(b) t BA = v A = Ax = − 0 ( ) = 0 ↓
24 EI 5
30 EI
0
SOLUTION (10.111)
a
A
M EI
Pa
2
Pa/2
A1
P
a
C
B
3a 2
x
A2
-
4a 3
Tangent at A
A
tB/A
1 Pa 2
2 EI
Pa 2
A2 = −2
EI
A1 =
vA = 0
θA = 0
(a) θ B / A = θ B − θ A0 = A1 − A2
Pa 2 2 Pa 2 3 Pa 2
−
=
2 EI
2 EI
EI
3a
4a
(b) t B / A = vB = A1 ( ) + A2 ( )
2
3
2
Pa 3a 2 Pa 2 2
23 Pa 3
( )−
( ⋅ 2a ) =
or
vB =
↓
2 EI 2
12 EI
EI 3
θB =
Excerpts from this work may be reproduced by instructors for distribution on a not-for-profit basis for testing or
instructional purposes only to students enrolled in courses for which the textbook has been adopted. Any other
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