Rigid Body Constraints with Shell structure and non-linear material law

Hello all,
I’m trying to simulate a shell structure with non-linear material law that is subjected to a displacement static step. The outer edge nodes are fixed boundary conditions. At the inner edge nodes a displacement is applied.

If I apply the displacement directly to inner edge (nodes) without using rigid body constraint, both the linear elastic and the non-linear elastic analysis run fine.

If I use instead the rigid body constraint with a reference point to the inner edge and run the same static step, only the linear elastic analysis runs fine but the non-linear elastic analysis fails to converge.

The reason I want to use the constraint with rigid body constraint is because I also want to simulate rotation and torque.

I have attached the *.pmx file of PrePoMax for the above described case. I’m using the latest version (V1.3.1.).

I very much appreciate any support on this topic.

Thanks!
Plastic Membrane Test.pmx (500.7 KB)

This is probably a problem with CalculiX. If you take a look at the Calculix Discourse group you will find that similar problems were reported but as far as I know, no universal solution was found. Instead of rigid-body connections users reported more success using a kinematic coupling connection.

Thank you for the quick reply. Is kinematic coupling implemented in PrePoMax?

It’s not yet implemented. Check this thread for details:

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