Mohr's circle with FREECAD

About the development of the FEM module/workbench.

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mrr
Posts: 3
Joined: Sat Sep 29, 2018 9:50 am

Mohr's circle with FREECAD

Postby mrr » Sat Sep 29, 2018 9:54 am

Hi all!

I'm new to the forum. Simple question: is it possible to get the Mohr's circle in a specific point of a solid? Let's say a beam where an axial force is acting. I have been searching in the forum but I did not find anything. Any hint is appreciated. Looking forward to your comments.

Kind regards,

MRR
fandaL
Posts: 320
Joined: Thu Jul 24, 2014 8:29 am

Re: Mohr's circle with FREECAD

Postby fandaL » Sat Sep 29, 2018 8:04 pm

With the FEM workbench one can make a stress analysis and check principal stresses from which you can easily construct the Mohr's circle.

If I step over how to make FE analysis, you can get stress results at point by:
- select result object and create pipeline (1)
- create Data at point (2) - under which you select the point and from the field rolet you chose the desired output
Data_at_point_icons.png
Data_at_point_icons.png (10.8 KiB) Viewed 397 times
chrisb
Posts: 14019
Joined: Tue Mar 17, 2015 9:14 am

Re: Mohr's circle with FREECAD

Postby chrisb » Sun Sep 30, 2018 5:28 pm

Moved to FEM forum.
mrr
Posts: 3
Joined: Sat Sep 29, 2018 9:50 am

Re: Mohr's circle with FREECAD

Postby mrr » Sun Oct 14, 2018 3:50 pm

Dear FandaL,

Sorry for my late reply. Thank you very much for your help. I will take this into practice with different examples.

Best regards.
User avatar
HarryvL
Posts: 819
Joined: Sat Jan 06, 2018 7:38 pm

Re: Mohr's circle with FREECAD

Postby HarryvL » Sun Oct 14, 2018 6:30 pm

By the way, in the equation editor of the result object you can plot the radius of Mohr circle by entering (P1-P3)/2 and the center is found by typing (P1+P3)/2.

In a 3D analysis every stress point has 3 Mohr Circles with radius R and center C as follows:

[R, C]= [(P1-P2)/2, (P1+P2)/2]
[R, C]= [(P2-P3)/2, (P2+P3)/2]
[R, C]= [(P1-P3)/2, (P1+P3)/2]

Where the last one is the largest and encircles the other two.
mrr
Posts: 3
Joined: Sat Sep 29, 2018 9:50 am

Re: Mohr's circle with FREECAD

Postby mrr » Sun Oct 14, 2018 7:13 pm

Ok! Thanks!