"mystery" formula from AISC spec ?

[TomBarsh]

Can someone identify this "mystery" formula purportedly from AISC for "unity" check? I was provided with this formula in some calculations; due to the context I assume they are referring to the combined load checks for beam-column. I can't identify this in the 9th or 13th Editions of the AISC "manual".

(Sma/Sa)+(0.85*S)/((1-Sma/Spex)*Sb)

 

[TehMightyEngineer]

Because there are a lot of S in there I'm going to assume 9th edition. I don't recognize it but I'm not as familiar with the 9th edition so that would make sense if it is 9th.

Professional and Structural Engineer (ME, NH)
American Concrete Industries

http://www.americanconcrete.com

 

[PMR06]

Looks a bit like H1-1 from 9th edition, but they are using Sma for fa, Sa for Fa, 0.85 is Cm, etc.

 

[TomBarsh]

PMR06, I do believe that you're right.

Thank you!

(and thank you all for participating)