260 7 The Force Method
7.2.A clamped-pinned beam is subjected to coupleM 0 at the roller support
B(Fig.P7.2). Find the reaction of supports and construct the bending moment
diagram.
l
M 0
A B
MA RA RB
Fig. P7.2
Ans:MAD0:5M 0 I RADRBD
3
2
M 0
l
7.3.Fixed-pinned beam is subjected to concentrated forceP at the midspan
(Fig.P7.3). Find the reaction of supports and construct the bending moment di-
agram.
l
A B
P 0.5l
C
MA
RA RB
Fig. P7.3
Ans:MAD
3
16
PlI MCD
5
32
PlI RBD
5
16
P.
7.4.The beamABwith clamped supportAand elastic supportBis subjected to uni-
formly distributed loadq; the stiffness coefficient of elastic support isk(Fig.P7.4).
The deflectionof supportB, reactionRBof this support and stiffness coefficientk
are related asDRB=k. Determine the reaction of supports. Consider two special
cases:kD/,kD 0.
A
q
B
k
l
l
Fig. P7.4
Ans:RBD
3
8
ql
1
1 C ̨
; ̨D
3 EI
kl^3