SFD & BMD OF SIMPLY SUPPORTED BEAM SUBJECTED TO UDL:
The total load carried by the span would be
= intensity of loading x length
= w x l
By symmetry the reactions at the end supports are each wl/2
If x is the distance of the section considered from the left hand end of the beam.
S.F at any X-section X-X is
Giving a straight relation, having a slope equal to the rate of loading or intensity of the loading.
The bending moment at the section x is found by treating the distributed load as acting at its centre of gravity, which at a distance of x/2 from the section
So the equation (2) when plotted against x gives rise to a parabolic curve and the shear force and bending moment can be drawn in the following way will appear as follows: