# Support reactions

#### davefrick1

Hello,
I have had the following question:

Determine the two support reactions at positions ‘A’ and ‘B’ for the following simply supported beam which is acted on by a uniformly distributed load (UDL) and two point loads.

UDL = 1.2K/n

6Kn 3Kn
A------------- ------------------- -----------B
2.1m 1.05m 1.05

(6 x 2.1) + (3 x 3.15) =R2 x 4.2m

(6 x 2.1) + (3 x 3.15) / 4.2 = R2

12.6 + 9.45 / 4.2 = R2

22.05 / 4.2m = R2

5.25kN = R2

R1 9 – 5.25 = 3.75kN

R1= 3.75kN
R2= 5.25kN

Is this correct? Im not sure!

Thanks
Dave

#### studiot

I am not clear as to the length of your beam or the positions of the point loads or how far along the beam the UDL extends.

But let's try a simple check shall we?

The sum of the vertical loads must equal the sum of the two vertical reactions.

Why have you said R1 and R2 not Ra and Rb ?

Be consistent with the question.

(1.2*length of UDL + 6 +3 ) = (3.75 +5.25)

If you are correct.

It is clear you are not since this implies zero UDL.

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