How do I draw shear and moment diagrams for a beam?

[jd747]

I'm not quite sure how to do this. I posted the diagram at my web site...the question is also there, but I typed it here just to give you an idea of what it is about. Thanks! The website:

http://www.geocities.com/jessparker502/


For this problem establish the x-axis with the origin at the left side of the beam and obtain the internal shear and moment as a function of x. Use the results to plot the shear and moment diagrams.

Draw the shear and moment diagrams for the beam (a) in terms of the parameters shown; (b) set p = 600lb, a = 5ft, b=7ft

 

[FredGarvin]

The shear diagram will look like two opposing rectangles, one on top of the axis, the other underneath. The shear forces will be equivilent to the reaction forces at each support, Pb/L on the left side and -Pa/L on the right. The transition between the two will be a vertical line at the point of load application.

The moment diagram will be a triangle with the max equivilent to Pab/L occurring at the point of load application.

This is doable if you start with the statics of the beam. Work out the reaction forces at each end. You could also do a search on shear/moment diagrams. They are printed quite often.