Brace Connection Design

[EBF]

I am working on the connection design for a special concentric brace frame. I am a little confused as to what forces i am supposed to use for the design of the welds and gusset plate.

The 2001 CBC Section 2211.4 specifies the lesser of:
1. Design Tensile strength of brace (I assume this means per AISC Specs, fPn = 0.9FyAg)
2. Force from load combinations 3-7 and 3-8 (0.9D+Em and 1.2D+fL+Em)
Then for gusset plates, it rspecifies the compressive design strength of the brace (similarly, fPc = 0.85FcrAg).

Is this correct? This is different from the AISC Seimic Provisions, which specifies nominal tensile strength instead of design tensile strength (P=RyFyAg), which is where i got confused...

 

[Taro]

Note that the 2001 CBC is based on the 1997 UBC which is based on the 1992 AISC seismic provisions which is now quite old. The AISC seismic provisions have been updated four times since 1992. So although the newer provisions are not specifically referenced by your governing building code, I believe it would be a good idea to consider them.