Simply Supported Beam : Overhang to One Side : Point Load : (Fig. 3.20)

Simply supported – a beam supported on the ends which are free to rotate and have no moment resistance

Over hanging – a simple beam extending beyond its support on one end.

Point loads are concentrated loads applied along the span of a member or the edge of a wall panel. Defining point loads may be accomplished graphically or in the spreadsheets.

In this example, one get clear idea how to calculate reactions when a simply supported beam is having point load overhang on one side of the support.

Reactions : Taking moments about B, we get
$R_{a}=\frac{W(L+a)}{L}$
$R_{B}&space;=&space;W-R_{A}&space;=&space;W-&space;\frac{W(L+a)}{L}&space;=&space;-\frac{W_{a}}{L}$

(i.e. acting downwards)

S.F.D. : Between C and A, S.F. =-W=constant

Between A and B, S.F. =

$-&space;W+R_{A}&space;=&space;-&space;W+&space;\frac{W(L+a)}{L}&space;=&space;\frac{W_{a}}{L}$

The S.F.D. is shown in Fig. 3.20 (b).

B.M.D. : Between C and A,

Mx=Wx, which gives MC=0 ; MA=Wa.

Between A and B,
$M_{x}=W_{x}-R_{A}(x-a)=W_{x}-\frac{W(L+a)}{L}(x-a)$
which gives   MA=Wa and MB=0.
The B.M.D. diagram is shown in Fig. 3.20 (c).