Erik Kostson
Ansys Employee

Not sure why that is but the below might be of help.
See this post (link below) and slide p. 10 in that presentation, that discusses aid for convergence .

Also be aware that is one of our TD examples (nr. 54). So follow the exact approach from that model.

That example (TD54) Using though Coupled damaged plasticity microplane models - so Men.-Wil. material (does not model damage only plasticity) model is quite different and hence will probably not give very similar results here most likely (e.g., the peak force will be perhaps close, but softening portion part of the load vs deflection curve will be very different)
Chapter 54: Reinforced Concrete Joint Analysis (

All the best