Roark's formula Table 26 case 1c not working

[JBlackhole]

Hi all

I copied the example from a Roark's datasheet (formula Table 26 case 1c) but it does not work. Could anyone point me in the right direction please?

Thanks

Regards

JXb

[alnstevens]

See attached.

stv

[JBlackhole]

Thanks. Much appreciated

[PhilipOakley]

There is one of the tables where there is a scaling error in indexing an array/vector.

If I remember it has a hard coded spacing factor in one of the equations where it should have used the particular variable.

It didn't show up in the handbook because the hard code and variable value were, if I remember right, 1". When one of my users put in his real values (e.g. 18mm) the array indexing of the results table went wrong/error/red.

Problem is I can't find the old email that told me where the problem was! (this was in the V11 vesrion)

Philip Oakley

[PhilipOakley]

In:
Table 24 Formulas for shear, moment and deflection of flat circular plates of constant thickness
Cases 2e - 2h Annular Plate With Uniformly Distributed Pressure q Over the Portion from ro to a; Outer Edge Fixed

just after:
Maximum deflection (magnitude):

Y[(r-b)*100/in,i := y(r,i)

The above is wrong (e.g. change the values of a & b to 300mm, 77mm to see error)

substituting for "in" with 'b' - use

Y[(r-b)*100/b,i := y(r,i)

same again for
Maximum slope (magnitude):
S[(r-b)*100/in,i := theta(r,i)

=>
S[(r-b)*100/b,i := theta(r,i)

Maximum radial moment (magnitude):
Maximum tangential moment (magnitude):
Maximum shear (magnitude):
Maximum radial bending stress (magnitude):
Maximum radial bending stress (magnitude): [Traverse!]

etc.


Philip Oakley

[mzeftel]

I just logged it for the next time Roarks is updated.

Mona