Is there some way to create a tube section in STAAD with different thickness of the horizontal and vertical sides?
Seems like you can only define on thickness that must be valid for all the sides.
Tubes and pipe sections are generally with same thickness. If you are looking for a built up box section with different wall thickness, you may use section wizard to create one. The below link may be helpful to understand how section wizard works.
Thanks & regards,
Global Technical Support