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RE: AISC 341-05 flexural strength of braced frame braces - I meant bases

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Sorry if someone talked about this recently and I wasn't tracking it but the
local municipality today gave a talk about changes to the 2006 IBC which they
just adopted. I have questions about braced frame bases for ordinary braced
frames and special braced frames.

AISC 341-05 Part 1 section 8.5c says That "the required flexural strength of
column bases, including their attachment to the foundation, shall be the
summation of the required strengths of the steel elements that are connected
to the column base as follows: (1) For diagonal bracing, the required
flexural strength sall be at least equal to the required strength of bracing
connectiosn for the SLRS...."

The commentary says you don't need to apply a column moment on braced frame
base plates because you are allowed to use special load combinations to
figure out the applied moment.

There is no "required flexural strength" for brace connections stated in
Section 14.1 for ordinary braced frames. 

Section 13.3 b for special concentrically braced frames says that if you meet
the tension strength requirement and detail brace gussets to buckle in their
weak axis then you don't need to design the brace connections for a flexural
strength 1.1*Ry*Mp of the brace.  In this case I am assuming the code is
saying required connection flexural strength is zero.

Do ordinary braced frame anchor bolts / bases need to be designed for moment
equal to the flexural strength of the braces framing into the base plate per
AISC 341-05 sections 14.1 and 8.5c?

Do special braced frame anchor bolts / bases when detailed to meet the
2*thickness setback and strength of the brace in tension have to be designed
for moment equal to the flexural strength of the brace framing into the base
plate per AISC 341-05 13.3b and 8.5c?

I went to a AISC 341-02 braced frame class where I noted in the class book
that for 2005 to fix the braced frame column and brace at the base in the
computer model and solve for the moment from the special load combinations.


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