Telechargé par Gingermon

sm10 13 14

publicité
_______________________________________________________________________
PROBLEMS (10.13 and 10.14) Solve Probs. 10.10 and 10.11, using the multiple-integration
approach.
SOLUTION (10.13)
y
PL
P
A
L/2
C
L/2
B
x
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 '''' = 0
EIv2 ''' = C5
EIv2 '' = C5 x + C6
1
EIv2 ' = C5 x 2 + C6 x + C7
2
1
1
EIv2 = C5 x 3 + C6 x 2 + C7 x + C8
6
2
(3)
(4)
Boundary conditions:
v1 '''(0) = 0 : C1 = 0
v1 ''(0) = PL : C2 = PL
L
v2 '''( ) = − P : C5 = − P
2
3
L
v2 ''( ) = PL : C6 = PL
2
2
1 2 3 2
v2 '( L) = 0 : − PL + PL + C7 = 0,
C7 = − PL2
2
2
3
5
PL 3 3
v2 ( L) = 0 : −
+ PL − PL3 + C8 = 0,
C8 = PL3
6
4
12
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.
Continuity conditions:
3
7
L
L
PL2
v1 '( ) = v2 '( ) :
+ C3 = − PL2 ,
C3 = − PL2
2
2
2
8
8
3
3
3
19
L
L
PL 7 PL
PL
,
v1 ( ) = v2 ( ) :
−
+ C4 =
C4 = − PL3
2
2
8
16
12
48
Then, Eqs.(1) through (4) yield the results given in solution of Prob. 10.10.
SOLUTION (10.14)
y
w
MA=2wa2
A
2a
C
a
B
x
RA=2wa
Segment AC
EIv1 '''' = − w
EIv1 ''' = − wx + C1
1
EIv1 '' = − wx 2 + C1 x + C2
2
1 3 1
EIv1 ' = − wx + C1 x 2 + C2 x + C3
6
2
1
1
1
EIv1 = − wx 4 + C1 x 3 + C2 x 2 + C3 x + C4
24
6
2
Segment BC
EIv2 '''' = 0
EIv2 ''' = C5
EIv2 '' = C5 x + C6
1
EIv2 ' = C5 x 2 + C6 x + C7
2
1
1
EIv2 = C5 x 3 + C6 x 2 + C7 x + C8
6
2
(1)
(2)
(3)
(4)
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.
Boundary conditions:
EIv1 '''(0) = −V = 2aw : C1 = 2aw
EIv1 ''(0) = −2aw2 : C2 = −2aw2
EIv1 '(0) = 0 : C3 = 0
EIv1 (0) = 0 : C4 = 0
Continuity conditions:
v1 '''(2a) = v2 '''(2a ) : C5 = 0
v1 ''(2a) = v2 ''(2a) : C6 = 0
4
v1 '(2a) = v2 '(2a) : − wa 3 = C7
3
8
2
v1 (2a ) = v2 (2a ) : − 2wa 4 = − wa 4 + C8 ,
C8 = wa 4
3
3
Then, Eqs.(1) through (4) yield the results given in solution of Prob. 10.11
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.
Téléchargement