Find Torsion Constant

[rbarton1]

All,

Is there a good way to find the torsional constant of a 2D shape?

Thanks!

[andrew.schroeder · Accepted solution]

Hi,

So I don't think that you'll get the torsional constant directly, but by taking a closed area of any shape, and creating a region of it, using the REGION command, you're able to then use the standard boolean commands like SUBTRACT, to create the 2D shape you're after.  Then, using the MASSPROP command, you can get the following info (for example):

---------------- REGIONS ----------------

Area: 3062.804
Perimeter: 237.172
Bounding box: X: 309808.130 -- 309883.418
Y: 4837554.582 -- 4837637.218
Centroid: X: 309847.847
Y: 4837587.436
Moments of inertia: X: 7.168E+16
Y: 2.940E+14
Product of inertia: XY: -4.591E+15
Radii of gyration: X: 4837587.436
Y: 309847.848
Principal moments and X-Y directions about centroid:
I: 1226113.922 along [0.842 -0.540]
J: 555195.453 along [0.540 0.842]

If this answers your question, please go a head and mark this solved.  Thanks!

[BushW]

Hello @rbarton1

I realize this thread is old but, did the reply of @andrew.schroeder help answer your question on how to find a torsion constant and did this work for you?

Please hit the ‘Accept as Solution’ button if/when relevant so, that others can more easily benefit from the information and thank you for doing so. 

Best Regards,

Wendell

[Anonymous]

"J" in the output of the MASSPROP command is not the torsional constant. It is the minimum principal moment of inertia.