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PROBLEM (*10.15) A cantilever beam is loaded as shown in Fig. P10.15. Using the multiple-integration method, determine:
(a) The equation of the elastic curve.
(b) The deflection at the free end.
(c) The reactions at the fixed support.
*SOLUTION
(a) EIv '''' = − w0 cos
EIv ''' = −(
2 w0 L
πx
2L
πx
+ C1
2L
4 w L2
πx
+ C1 x + C2
EIv '' = ( 02 ) cos
π
2L
8w L3
πx 1
+ C1 x 2 + C2 x + C3
EIv ' = ( 03 ) sin
π
2L 2
4
16w0 L
πx 1
1
+ C1 x 3 + C2 x 2 + C3 x + C4
) cos
EIv = −(
4
π
2L 6
2
π
) sin
Boundary conditions:
16w0 L4
v(0) = 0 : C4 =
4
π
v '(0) = 0 : C3 = 0
2w L
v(0) ''' = 0 : C1 = 0
π
v(0) '' = 0 : C2 = −
2 w0 L2
π
Therefore,
w
πx
− π 3 Lx3 + 3π 3 L2 x 2 − 48 L4 ]
v = − 40 [48L4 cos
3π EI
2L
(b) Let x=L in the above expression:
w
w L4
vB = − 20 (−π 3 L4 + 3π 3 L4 − 48L4 ) = 0.04795 0 ↓
3π EI
EI
(c) Expressions for shear & moment are
2w L
πx
V = 0 (1 − sin )
π
2L
2w0 L
πx
M = 2 (cos
+ π x − π L)
π
2L
Continued on next slide
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These result in, for x=0:
2w L
RA = 0 ↑
π
2(π − 2) w0 L2
MA =
π2
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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