prequalified connections?

[SteelPE]

I am looking into a building that was designed using the 2002 AISC Seismic Provisions. I don’t really want to get into the situation but I have been asked about the possibility of taking over the design.

The structure was designed with a LFRS consisting of Intermediate Moment Frames (as indicated on the note sheet). In order to use this type of a LFRS the connection must be “prequalified” or the connection must be tested. I know the 2005 AISC Seismic Provisions list some prequalified connections in the appendix (a reduced beam section and bolted end plate connections). However, there are no prequalified connections that I can find in the 02 spec. Is there another document that I am missing that would give me prequalified connections for this specification?

 

[SteelPE]

Certainly people must use moment frame systems with R>3?

 

[frv]

I may be pulling this out of where the sun don't shine, but I seem to remember hearing at the NCSEA Winter institute a few years ago that there were, in fact, no prequalified moment connections in the 2002 manual but that the research was being conducted when it was published.

In other words, the reference to prequalified moment connections in the 2002 code was in anticipation of these "prequalified" connections being made available shortly thereafter.

If my memory serves me correct on the previous points, then I believe you should be able to use the prequalified connections in the 2005 manual to satisfy the requirements of the 2002 manual.

 

[SteelPE]

Thanks for replying.

That makes some sense and may help a little. However, the 2005 spec only has 2 different type of connections, the Reduced Beam Section and the Bolted End Plate Connection. Unfortunately this is not the connection that was used in the original design. The original design calls for directly welded flanges with no reduction in the beam flange size (therefore no RBS). I know there is another spec coming that will add to the list of "prequalified" connections... but I don't think it's out yet.

I am wondering how you could justify using a IMF with no real way of designing the system?

 

[frv]

Have you searched AISC for additional prequalified connections?

The way I understand it is that they will publish them as they get results back and include a comprehensive list each time the manual is published..

 

[frv]

See the following link:

http://www.aisc.org/WorkArea/showcontent.aspx?id=17176

 

[SteelPE]

frv

Thanks for the info but that is the 358-05 spec which I already have. I have briefly looked on the AISC website and haven't found anything (of course I only looked briefly). I will do another more intensive search.

 

[SteelPE]

frv

I was able to find the supplement to the 358-05 you listed above:

http://www.aisc.org/WorkArea/showcontent.aspx?id=21220

Hopefully this will have the information I am looking for.