I am modeling a section of the deck of a ship with shells.  The underside of the deck is supported by a combination of angles, flange plates, and bulkheads.  I created split lines across the entire deck surface whereever there was a member to facilitate meshing and bonding.  I then added the deck structure and a piece of equipment into an assembly file and set up the simulation.  Global contact is set to bonded.  It keeps telling me the model is unstable.  When I turn on soft springs and inertial damping to get it to run and see what is failing it shows that half of the deck plate is peeling up in several places and numerous bulkheads are just flopping around like a wet noodle.  I have confirmed in the shell model that all of the surfaces are indeed connected with no gaps.  What has me so confused is that in some areas the deck plate is staying contected and other bulkheads are also staying in place.  Anyone else encountered shells flying apart, even after you inserted a split line to facilitate the meshing?  Do I have to manually go in and apply bonding to each joint?  There is probably well over 100 seams that I would have to do this to so I really don't want to head down that path.

Unfortunately I cannot share the files or screen shots due to an NDA with my client.