AASHTO LRFD Bridge Design Code Eq. 6.9.4.3.1-1 p.6-77

In the design of steel columns made of built-up sections, we may have to modify the slenderness ratio for intermediate connectors that are welded or fully tensioned bolted, as per equation Eq. 6.9.4.3.1-1 p.6-76. On page 6-77, there is another equation for other types of intermediate connectors on built-up members, including riveted connectors on existing bridges, Eq. C6.9.4.3.1-1 p.6-77 should instead be used:

(KL/r)_modified = √((KL/r)_o² + (a/r_i)² s)

Does anyone here knows what does the "s" mean for ? In the current edition of the code, I could not locate any explanation about this variable. I checked the AISC Code for an equivalent equation. In AISC, the equations are almost the same except the variable "s". If there is someone who has been using this equation in the actual design, please let us know your understanding on the equation, particularly, the variable: "s".

Thank you.
-=≡∃POKAREL::.

WebSite: http://www.SEOA.COM/
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