AISC J10.4 Web Sidesway Buckling

[Bobby46]

I'm doing some checks to size transverse web stiffeners for a wide flange beam. I was hoping to get some clarification on the web sidesway buckling check. Specifically, I am looking at Cr factor. AISC directs you to select a Cr factor based on the ratio 1.5Ma to My. I can't find a definition for My anywhere.

Is this intended to be a yielding moment? Would this be the plastic moment or should it be calculated with an elastic section modulus?

Is the "y" intended to indicate the weak axis of the beam (i.e. some measure of when the beam kicks out sideways)?

Something else entirely?

 

[JAE]

My = Fy x S



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[JAE]

Sorry...yes - the My is the yielding moment and based on the Section Modulus, Sx, of the major axis in this case.

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[WinelandV]

In the AISC 360 (Specification for Structural Steel Buildings), between the Table of Contents and Chapter A, there are three mini-sections: symbols, glossary, and abbreviations. Any of the symbols used in the spec should be listed in the symbols section, which is very helpful the symbol (like My) isn't defined within the section you're looking at.

 

[Bobby46]

Thanks JAE.

Thanks windlandv. I didn't realize there was a symbols section. I looked in the General Nomenclature section before the index, but I didn't see it listed.