Problem 8.32
A simply supported beam with two equal forces applied equidistant from the
supports is called four-point bending. This loading arrangement is commonly
used for testing beams in a laboratory.
(a)
Determine the shear and moment as functions of position. Express your
answers in terms of parameters such as
P
,
L
, etc. Draw the shear and
moment diagrams.
(b)
Comment on any interesting features the shear and moment display in the
region between points Band C.
Solution
Part (a) By inspection (or by using PMD0,PFxD0, and PFyD0), the reactions are
We take a cut at an arbitrary position between points
A
and
B
and draw the FBD to the
left of the cut to determine the shear and moment as functions of position for 0xL
3.
XFyD0WPVD0; (2)
)MDPL
3:(10)