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Special Truss Moment Frames - AISC Seismic Prov

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I have a question about 12.4 on page 24 of the 2002 AIC Seismic Provisions.  It has to do with the Non-special segment members.  Here goes...what the heck is 12.4 telling me to do?

"Members and connections of STMF, except those in the special segment defined in Section 12.2, shall have a Design Strength to resist the effects of load combinations stipulated by the Applicable Building Code, replacing the earthquake load term E with the lateral loads necessary to develop the expected vertical nominal shear strength in the special segment Vne given as: ..." and then it gives a formula where all the variables are moment, tension, and compression strengths of the truss members.

Here is what I think it means.
Design the truss as you usually would and get the Vne based on the members you are using in the special section of the truss.  Do another frame analysis and iterate until the shear in the special section equals Vne.  This is the lateral load you use in your E for the load combinations.  Recheck truss.  When you do this you will likely get different member sizes for the special section and then you have to start the whole process over again.

I really hope this isn't correct, but that's what it sounds like.  Have any of you run into this.

PS.  This project is in the Memphis area and is IBC 2000

John C. Jones, PE
Barnett Associates
Pell City, AL
205-884-5334
205-884-0099 (fax)


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