Reaction forces on composites

General Questions
1

Hi,

Does RF reaction forces work for composites?

Do they need some special set up?

Regards

2

Do you mean composite shell sections ? I haven’t noticed any issues with reaction forces in such cases (although I rarely use composite shells in CalculiX). Do you have specific concerns in mind ?

3

-I don’t recall having any issue too but now I’m not sure If I have ask for RF on composite shell before. Doesn’t work. RF, section print, everything is empty. (0)

4

RF history output works in a simple test:

RF
RF995×615 16.2 KB

5

Isn’t those forces shown in the GUI the same forces? The one on top is all zero.

imagen
imagen238×347 17.3 KB

6

Indeed FORC field output is zero in my test too. But RF history output is non-zero and correct.

7

Thanks. I will try that way.

8

Can I get the .pmx file to see if there are really 0 in the .frd?

9

Sure, here it is:

Composite.pmx (1.0 MB)

GraphiX shows 0 too.

10

Aha OK, so it is probably 0. But I will check it.

11

Just found it in the doc:

The restrictions on this kind of composite element are right now:
• can only be used for S8R and S6 elements
• reaction forces (RF) cannot be requested in the .frd file.
• the use of *NODAL THICKNESS is not allowed
• the error estimators cannot be used.

So you can only get RF from .dat file (history output) in this case.

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