Web stiffeners in columns at moment connections (in close proximity)

[pwmiller54]

I am an engineer working for a steel fabricator. We are working on a job where the EOR is asking for web stiffeners at every moment connection. That in itself is not a problem. My issue is that I have beams with MCs coming into W-shape columns on all 4 sides with 2 sides being 2.5" lower (joist & deck floor system). He's asking for stiffeners in column at top & bottom flanges on all sides. So, at the top flange, I'll have stiffeners roughly 2.5" apart on the column web. I can't find anywhere in the manuals that says I can eliminate one set due to the close proximity of another set of stiffeners. Does that idea exist? On our own jobs, we've always made the judgment that if the stiffeners are that close that they serve the dual purpose. Am I out in left field in my thinking? Is there anywhere in a design guide or manual to back this up? Please help. Thanks.

Paul

 

[structSU10]

There is a discussion in AISC Design Guide 13 section 5.1. They discuss that an offset stiffener could be treated with a strength reduction - its 100% capacity with 0" eccentricty to 65% capacity for a 2" eccentricity. It also discusses sloped stiffeners, or 2 close partial depth stiffeners.

 

[pwmiller54]

That helps. Thanks.