I would like to prevent the interprenetation of solids, that are "linked" by fasteners...
You have any idea?
The other option would be to use a bonded interface - that would prevent interpenetration, but would also prevent separation.
In some other analysis package there's a sort of 'tied' interface, which keeps parts in contant but allows them to slide, but I'm not aware of anything equivalent in Mechanica.
By definition, if you want surfaces to be able to separate but not penetrate, that's a non-linearity...
The fix separation option for the fastener is preventing the parts from
separating at locations where they should separate. Hence, the results
for this analysis ... inaccurate. You should turn off the fix separation
option for the fastener and ... introduce a contact interface
between the parts that are connected by the fastener."