Failure of member due to eqn. H3-6(AISC)

[Vipin Satheesh]

Attached is the staad model of a cladding support I have been designing. I cant seem to shake off the failure of two members due to H3-6(combined torsion and flexure).
I have tried releasing moment as well as providing braces and changing member size.
Please can anyone look into it and find a solution.

 

[WARose]

Definitely one of the most odd-ball models I've seen. In any case, I couldn't get any sizes to work either. I suspect it has something to do with the fact this is a enforced displacement model and these members are on a curve. I.e. the stiffer the member is, the more force that gets sucked in (for a lack of a better way to put it). Of course, going with the smaller members.....it didn't work either. I think you are probably going to need more releases.

Something that jumped out at me in the post-processing (aside from a million warnings): no stresses in any of the plates. Speaking of the plates, they are extremely thin.

What is this thing anyway?

[red]EDIT:[/red] Adding releases, I got it to run with no failures.