Telechargé par Gingermon

sm12 47

publicité
________________________________________________________________________
PROBLEM (12.47) A cantilever beam is loaded as shown in Fig. P12.46. Apply Castigliano’s
theorem to determine the deflection vB of the free end.
SOLUTION
x
x
P
a
A
C
b
Q
B
L
Segment BC
M 1 = −Qx
∂M 1 ∂Q = − x
Segment AC
M 2 = −Qx − P( x − b),
So,
vB = ∫
∂M 2
= −x
∂Q
M ∂M
dx
EI ∂Q
Let Q=0:
1 L
− P( x − b)(− x)dx
EI ∫b
1 1
Pb 2 2
[ P( L3 − b3 ) −
( L − b )]
=
2
EI 3
vB =
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