Finite elements along bar element

[ByrnePM]

I would like to understand the number of finitie elements that are automatically created along a bar element in order to generate a bending moment diagram ?

And also is it possible to control the number of elements ?

I have found help file which talks about the "maximum length of bar element for division" but this only related to specific analysis types .

I am interested in a standard static analysis of simple bar for instance (see pic)

How does robot calculated the Bending moment diagram ? Is there a defined no. of finite element points along the bar ?

Thanks in advance

[Artur.Kosakowski]

Hi @ByrnePM

Unless you run elasto-plastic analysis or have structure geometry modification (check the corresponding part of Help) there are no calculation elements generated along a bar unless you define nodes along the bar. You can see if they are created displaying their numbers (after model generation). 

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

[ByrnePM]

Hi @Artur.Kosakowski,

Thanks for the reply,

Yes, this was my understanding from help file,

So, based on this is there any info you could point me to about how ROBOT  calculates internal forces along a bar element (for instance the bending moment diagram) ?

Is this not done by dividing the bar into finite elements? (of which there are a default number?)

Thanks,

[Artur.Kosakowski · Accepted solution]

Hi @ByrnePM

In short it is based on displacements and rotations of the end nodes and integration of load defined along a bar. In details check (look for Timoshenko bar element type):

http://www-g.eng.cam.ac.uk/csml/teaching/4d9/4D9_handout2.pdf

http://kis.tu.kielce.pl//mo/COLORADO_NFEM/colorado/NFEM.Ch09.pdf

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

[me1205377]

hi @Artur.Kosakowski does generating nodes along  the bar with/without  edge division both  have the same effect ?

by that i mean creation of finite elements along the bar