Civil Engineering Reference
In-Depth Information
The principle of virtual work is, in fact, an alternative to Eq. (2.10) for specifying the
necessary conditions for a system of coplanar forces to be in equilibrium. To illustrate
the truth of this we shall consider the calculation of the support reactions in a simple
beam.
E
XAMPLE
15.1
Calculate the support reactions in the simply supported beam
shown in Fig. 15.4.
W
A
B
C
R
A
R
C
a
b
L
(a)
W
C
B
v,C
v,B
A
C
B
R
C
R
A
(b)
W
C
B
u
v
A
v
u
v
L
v
u
v
a
v
C
A
B
R
A
R
C
a
b
F
IGURE
15.4
Use of
the principle of
virtual work to
calculate support
reactions
L
(c)
Only a vertical load is applied to the beam so that only vertical reactions,
R
A
and
R
C
,
are produced.
