KP, glad I could help. Another issue I saw, though not a major one, is that you released all moments at both ends of the longitudinal beams. That's introduces a possible instability. Imagine apply a torque to one of these beams. It would spin freely. Of course, STAAD (and any linear analysis program) can't simulate free spinning. Instead you get an instability warning. I generally don't release MX for shear connections. Yes, they do have a reduced stiffness but usually there is nothing trying to twist them so I don't worry about it. Just take a look at the torsion and see if there are any large values. If so, then you have to decide the best approach to coping with them.
Also, a modeling note. You don't have to have a separate member release command (like START MY MZ) for each member. You can assign a list a members to each unique release type. This is much faster than having a separate line for each end of each member.
Good luck as you learn STAAD.
Also, a modeling note. You don't have to have a separate member release command (like START MY MZ) for each member. You can assign a list a members to each unique release type. This is much faster than having a separate line for each end of each member.
Good luck as you learn STAAD.