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PROBLEMS (10.22 and 10.23) Redo Probs. 10.18 and 10.19, using the multiple-integration
method.
SOLUTION (10.22)
y
M0
A
a
C
L
RA=M0/L
B
b
x
RB= M0/L
Segment AC
EIv1 '''' = 0
EIv1 ''' = C1 = −
M0
L
0
M0
x + C2
L
M
EIv1 ' = − 0 x 2 + C3
2L
M0 3
EIv1 = −
x + C3 x + C4
6L
EIv1 '' = −
(1)
(2)
Segment BC
EIv2 '''' = 0
EIv2 ''' = C5 = −
M0
L
M0
x + C6
EIv2 ''( L) = 0,
L
M
EIv2 ' = − 0 x 2 + M 0 x + C7
2L
M0 3 1
EIv2 = −
x + M 0 x 2 + C7 x + C8
6L
2
EIv2 '' = −
C6 = M 0
(3)
Boundary and continuity conditions:
v1 (0) = 0 : C4 = 0
M 0 L2
+ C7 L + C8 = 0
3
v1 '(a ) = v2 '(a ) : C3 = M 0 a + C7
1
v1 (a ) = v2 (a) : C3 a = M 0 a + C7 a + C8
2
v2 ( L) = 0 :
Continued on next slide
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Solving,
M0L
M 0a2
C3 = −
+ M 0a −
3
2L
2
M L M a
M a2
C7 = − 0 − 0
C8 = 0
3
2L
2
Then, Eqs.(1) through (3) yield the results given in solution of Prob.10.18.
SOLUTION (10.23)
y
P
A
k
a
C
a
B
x
P/2
P/2
Segment AC
0
P
Px
EIv1 ''' =
EIv1 '' =
+ C1
2
2
1 2
EIv1 ' = Px + C2
4
1
EIv1 = Px 3 + C2 x + C3
12
Segment BC
P
EIv2 ''' = −
2
(1)
(2)
1
EIv2 '' = − Px + C4
2
EIv2 ''(2a) = 0 : C4 = Pa,
1
EIv2 '' = − Px + Pa
2
1
EIv2 ' = − Px 2 + Pax + C5
4
1
1
EIv2 = − Px3 + Pax 2 + C5 x + C6
12
2
Boundary & continuity conditions:
P
PEI
v1 (0) = − : C3 = −
2k
2k
C6 2 2
v2 (2a ) = 0 : C5 = − − Pa
2a 3
1
v1 '(a) = v2 '(a) : C2 = Pa 2 + C5
2
1
PEI
v1 (a ) = v2 (a) : C6 = Pa 3 −
6
2k
(3)
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.
Solving,
3
PEI
1
PEI
C5 = − Pa 2 +
C2 = − Pa 2 +
4
4ak
4
4ak
Then, Eqs.(1) through (3) yield the results given in solution of Prob.10.19.
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
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