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actual reaction (was re: asd vs. lrfd)

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Title: ASD vs LRFD
>   In seminars sponsored by the AISC on connection design, 
> they repeatedly state that more economical connections 
> can be provided if the reactions are provided. I agree with this, 
> but because changes frequently occur after the building is 
> completed, I would rather pay for a full depth connection now 
> than save a couple of bolts during construction and have to 
> change/modify the connection later (when the facility is in production). 
 
The point of specifying actual reactions is not to save a couple of bolts or reduce the welds a little bit. Rather, it is to prevent things like W18s with such arbitrarily large (and overstated) end reactions that a plate has to be welded to the bottom flange with the bottom flange cut away flush to allow a 9-bolt-deep connection to be made. What should be a $50 detail becomes a $500 or $1000 or worse detail. It may also be unsafe to give arbitrary loads in charts or by other means, such as in cases with concentrated loads.
 
That is an example for a shear connection and I can draw many, many parallels for other types of connections.
 
Charlie
 
P.S. The unified specification means debates about ASD and LRFD will soon be meaningless. They're almost meaningless now in the sense that there really is very little difference between the methods if you disect them each as I've had to do for the development of the unified specification effort. The only real differences center on the load combinations used, effects of improvements that have been made in LRFD since the last ASD work, and the familiarity with one or the other that is personal to each of us.
 
If you're interested, you can read more about the unified spec here:
 
    http://www.aisc.org/msc/0109_02_unifiedspec.pdf