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PROBLEMS (10.20 and 10.21) Redo Probs. 10.16 and 10.17, using the multiple-integration
method.
SOLUTION (10.20)
y
w0
x
( L − x) = w0 − w0
L
L
wo
A
w0 L
3
x
x
B
L-x
w0 L
6
x
x2
w0 ,
EIv ''' = − w0 x +
w0 + C1
2L
L
1
x3
EIv '' = − w0 x 2 +
w0 + C1 x + C2
2
6L
1
1
x4
3
EIv ' = − w0 x +
w0 + C1 x 2 + C2 x + C3
6
24 L
2
5
1
x
1
1
EIv = − w0 x 4 +
w0 + C1 x3 + C2 x 2 + C3 x + C4
24
120 L
6
2
EIv '''' = − w0 +
(1)
(2)
Boundary conditions:
wL
wL
v '''(0) = −V = 0 : C1 = 0
3
3
v ''(0) = 0 : C2 = 0
v(0) = 0 : C4 = 0
w0 L4 w0 L4 w0 L4
w L3
+
+
+ C3 L = 0,
C3 = − 0
24
120
18
45
Then, Eqs.(1) and (2) yield the results given in solution of Prob.10.16.
v( L) = 0 : −
Continued on next slide
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SOLUTION (10.21)
y
A
wL/8
w
L/2
C
L/2
B
x
3wL/8
Segment AC
EIv1 '''' = 0
EIv1 ''' = C1
EIv1 '' = C1 x + C2
1
EIv1 ' = C1 x 2 + C2 x + C3
2
1
1
EIv1 = C1 x 3 + C2 x 2 + C3 x + C4
6
2
(1)
(2)
Segment BC
EIv2 '''' = − w0
EIv2 ''' = − w0 x + C5
1
EIv2 '' = − w0 x 2 + C5 x + C6
2
1
1
EIv2 ' = − w0 x 3 + C5 x 2 + C6 x + C7
6
2
1
1
1
EIv2 = − w0 x 4 + C5 x 3 + C6 x 2 + C7 x + C8
24
6
2
Boundary and continuity conditions:
EIv1 (0) = 0 : C4 = 0
1
1
EIv1 '''(0) = −V = wL : C1 = wL
8
8
EIv1 ''(0) = 0 : C2 = 0
3
3
EIv2 '''( L) = − wL : − w0 L + C5 = wL,
8
8
1 2
EIv2 ''( L) = 0 : C6 = − wL
8
(3)
5
C5 = wL
8
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.
and
1
L
L
wL3
wL3
v1 '( ) = v2 '( ) :
+ C3 = −
wL3 + C7 ,
C7 = C3 +
(4)
2
2
64
192
48
L
L
wL4 wL4
wL4
v1 ( ) = v2 ( ) :
=
+ C8 ,
C8 = −
2
2
384 192
384
3
wL
v2 ( L) = 0 : C7 =
384
7 wL3
Equation (4): C3 = −
128
Then, Eqs.(1) through (3) yield the results given in the solution of Prob. 10.17.
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.
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