Erik Kostson
Ansys Employee

Have not written since I do not know what is going on here.
THe model shown in the sample workflow I created worked fine so again I do not know what the issue is - again I can appreciate that you are modelling something else.
Have in mind that the sample workflow is just a sample and nothing else (it does not guarantee that this workflow is always working and that one will not encounter any issues (concrete modelling can be very hard in terms of getting convergence), furthermore I provided the workflow but it does not mean that I will resolve any issues on any models that use this, it is just to highlight a possible way which I have found works good for RC structure).

What I would suggest though is to remove that diagonal edge you have since you do not need (in my example it is there because of the BC which were aligned like that across the slab) - also make sure you use 2021 R1 or R2.

That is all I can add and suggest (if this does not work I can not help anymore).
Also if not removed, remove the command snippet, from the solution (as mentioned before the keyopt, and tb commands go under the concrete slab part in the geom tree, just as you have done - if it contains neqit command that is not really needed, at least I did not use it in the example).

Thank you and all the best