Depends on how much... in an extreme, you can weld plates across the toes of the H section.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

Thank you for your reply dik.

The illustration of plan view structure is shown below, it is an offshore structure. (I guess my weak axis bending concept is correct.)



Thank you very much.

I reinforced one of the auto manufacturer's plant buildings in Windsor about 30 years back. First floor to second floor height was about 80'. They were adding a large 30'dia+ VOC duct for the width of the roof... about 300' above along
the top of the roof. There was added load and added wind load. I had to reinforce the columns using that approach. It adds steel and reduces the kl/r a bunch.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

Thank you dik for your reply.

However I would like to clarify on the diagram, sorry that I did not make it clear.


I would like to find ways to reinforce on the weak axis of the primary beam due to wave load.

Thank you very much.

What are those 'things' with the arrows on them and how are they attached? Joists? Can you add a plate toe to toe on one side of each beam? Can you do anything to provide diaphragm action for the overall floor plate and eliminate the bending in the beams? Can you use sheet metal strips, say 3" or 8" wide. diagonally from corner to corner attached to whatever flooring.

I had a project about 30 years back... steel building with CFS studs and a veneer wall. Shortly before opening, they discovered the one set of steel angle cross-bracing was left out. The exterior wall was nearly constructed. The cross-bracing was replaced with sheet metal strips and 'pop rivets'... first time I ever used pop rivets structurally.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

Are you stiffening an existing member, or scheming up details for a new design?
Plates/ flat bars welded between flanges or flat on flanges, truss-work across the square come to mind.
Investigate higher-grade steel members if available.
Switch to square tubing in lieu of wide-flange beams.
Fixed/moment connection at the corners.

Add some form of diaphragm? could be as basic as some diagonal braces or detailing any flooring over the beams appropriately to address the out of plane concern.

That seems to be the only way if strengthening the members isn't possible (which you're inferring?).

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