I have a situation where I need to reinforce an existing 18' long column to increase it's axial capacity, which of course is controlled by minor axis buckling. One side of the column is partially embedded in a block wall, so I have access from one side only... the edge of the flanges and the web. I'm thinking of taking maybe two eight foot long plates (1' shy top and bottom), and stitch welding them to the edges of the exposed flanges. The plate width would be slightly narrower than the depth of the column to allow welding.
I have several questions:
1. Is stitch welding sufficient to enhance ry?
2. How do you size the welds, other than making sure the reinforcing plate does not buckle between welds?
3. Do the two stacked plates need to be full pen welded at the splice?
4. Can you count on the area of the added plate to reduce the P/A (for added loads only), as well as enhance the Fa because of KL/ry is less?
I thought about adding a kicker down from the roof beam that frames into the web at the top, but installing a brace would be difficult in the restricted space available.
I have several questions:
1. Is stitch welding sufficient to enhance ry?
2. How do you size the welds, other than making sure the reinforcing plate does not buckle between welds?
3. Do the two stacked plates need to be full pen welded at the splice?
4. Can you count on the area of the added plate to reduce the P/A (for added loads only), as well as enhance the Fa because of KL/ry is less?
I thought about adding a kicker down from the roof beam that frames into the web at the top, but installing a brace would be difficult in the restricted space available.