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Re: drywall type shearwalls- l

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I think the consensus here is that gypsum wallboard for seismic resistance is
bad, but I'll add my 2 cents.  One of the emergency ordinances in the city of
Los Angeles after Northridge banned gypsum wallboard and stucco shearwalls.  I
don't know if that has been carried through into the latest LA Building code,
but the reasoning (as it was explained at one of the SEAOSC seminars) was that
the code values at the time ('91 UBC) were based on unidirectional testing,
rather than cyclic, so they gave a very unrealistic capacity.

Chris Willcox

dcarroll wrote:

> In the past, we have always used plywood or metal strap brcg for
> shearwalls--
>
> But now we have a project where we HAVE to use drywall on metal studs as The
> Shear Resisting system .
>
> So my questions  run like this:
>
> 1.  How many Structurals out there feel comfortable using drywall for
> lateral (shear) resistance ?   {esp for seismic forces?___}
>
> 2.  ICBO lists tables where 100 plf seems to be a typical value :    a) Is
> this conservative or "liberal"?__________
> b)  Doesn't aspect ratio influence this number?_________?           c) What
> is the best design aid/reference for this system?
>
> 3.  Is metal stud stronger or no different from wood stud?
>
> 4.  Table seems to be based around wood studs using "cooler" nails-- what's
> this ??
>      I have metal studs-- I assume  ordinary drywall screws are OK?
>
> 5.  Are there some (major) unwritten Do's and Don'ts with this system?
>      (I will put this into a spec--   Does anybody have spec or design expl
> they can fax me ?/
>           my fax is 859_278-6060 attn David )
>
> Thanks in advance for ANY input--
>  P.S.  I need it ASAP
>