RE Bending moment and shear force diagram

Forum|Forum|11 years ago
September 2, 2014
3 replies
4494 views

Almost there guys.

I've manage to draw the shear force diagram from some given numbers, I'm now trying to plot the bending moment diagram but for some reason I'm getting an error on the moment axis.

any suggestions or assistance would be greatly appreciated.

1_Beam-Designtest-xmcd.zip

Other

R

RichardJ

19-Tanzanite

M is a function of x, so you should have x.m on one axis and M(x.m) on the other.

However, you have an error in the definition of M. W is a two element vector, but i ranges from 1 to 4, so the index is out of range.

G

gbradley

Author

1-Visitor

Thanks Richard, I'll have a look and get back to you

F

Fred_Kohlhepp

23-Emerald I

There's an easier, more general way to do this type of problem; vectors for plotting are poor for this.

1_Beam-reDesign-test-xmcd.zip

G

gbradley

Author

1-Visitor

Thanks Fred, although the way you've shown is the generally way to do this. with the vectors, the mathcad sheet can be given to someone with hardly any knowledge of mathcad. so the only thing they need to do is add as many point loads and UDL's to the span of the beam and the sheet will work it out.

They don't need to go into the formula's to re write the equation.

See new attachment with the original problem

1_Beam-Designtest-xmcd.zip

F

Fred_Kohlhepp

23-Emerald I

So your challenge is to write the functions from the vectors . . .

G

gbradley

Author

1-Visitor

Thanks Guys, shear force and bending moment diagram drawn, two more questions, how can a invert the graph so the bending moment and shear are the other way?

and how do I change the units to kN.m and m to the graph.. you can see the numbers at present are not correct

model attached

1_Beam-Design_new-xmcd.zip