Mortar contact simple example

[ANYS]

@FEAnalyst

Please do so, I will also notify Guido if he doesn’t react anytime soon once the GitHub issue is posted.

I almost always use the SI(mm) system, and I had convergence issues with Mortar contact in several cases, but it might be another problem - probably poor convergence of the Lagrange multipliers in general, combined with worse optimization than e.g. in Abaqus.

Still, I will look for some examples too and maybe we can help Guido further improve the Mortar contact algorithm.

Would be nice if you can find some failing file and post so I can try to rule out causes and corner the possible culprit. I have seen some users in the forum with problems when microns are involve. Here we are talking about element sizes of mm which is much more common on refined areas.

[FEAnalyst]

Sure, I will share them in the CalculiX forum thread and then in the GitHub issue once confirmed. My experience with this type of contact is really bad, so I’ll definitely find something worth sharing. I hope a bug will be identified and fixed, or at least we will find out how to avoid convergence problems with this type of contact - maybe it needs some special considerations regarding e.g. element type selection or contact stiffness settings.

[FEAnalyst]

@supreeth

The stress strain curve for concrete is not linear.
so the model does not considered this non linear property to get the stress values.

Why concrete ? The cubes are made of steel. This thread is not about mortar as used in masonry, but about contact algorithm named Mortar.

[supreeth]

Ohh sorry I thought concrete mortor