I am trying to get an idea of how much load / weight (2) 9 foot long piece of 3.5" x 3.5" x 1/4" thick hollow square steel tubing can support when used vertically as a column. The columns would be place at each end of a 17' engineered lumber beam(Glulam) There will be 3.5" x 5.5" x 1/4" flat stock at the top and bottom of the pier which would be welded the tube. The tube would be secured using anchors to a concrete footing at the bottom and secured to the bottom of a glulam using structural fasteners.
Just for the sake of concentrating specifically on the load bearing capacity of the steel columns. The beam is supporting a residential living area with a live load of 40 psf and a dead load of 20 psf.