It seems to me that AISC unity check structural module from Caesar II, version 5.20 does not work properly.
For an element, normal carbon steel, with:
Unsupported Axial Length = 1000 mm
Axial Member Force = 10 N
Unsupported In-Plane Bending Length = 1000 mm
In-Plane Bending Moment = 10 Nm
Unsupported Out-Plane Bending Length = 1000 mm
Out-Plane Bending Moment = 10 Nm
I’ve got failing even with W12x190 member, which is hard to believe…
Please advice

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