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Re: 3/8 inch shear panels

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Yes, the design load on the hd is about 5 to 6 kips but the ultimate
load is about 12 to 15 kips; not an insignificant load but not an
unreasonable load.  Your footing & connection has to be able to handle
the ultimate loads.   Shear is no problem but uplift/pullout might be.

If you've got to use 3/8 STR I with 8d @ 2"  maybe you're "stretching"
the envelope.  How about using more reasonably nailed walls (8d at 3" or
4")  {These work great I've tested LOTS of them}and adding another one.
Or a longer wall.  IMO 8d @ 2" is asking for trouble.

There is nothing wrong with 3/8" plywood shear walls properly designed &
detailed.  Just use reasonable nailing schedules.

Reference June 1998 EERI paper - Cyclic Load Testing of Woof-Framed,
Plywood Sheathed Shear Walls Using ASTM 564 and Three Loading Sequences.
All the plywood was 3/8 & all the nailing was at 3" oc.  (Unfortunately
units in the paper are metric).  While you at take a look at SEAOC 1995
& 1996 Annual Convention Proceedings >>>>> lots more plywood panel test
data.

 Robert Kazanjy, PE  **Disclaimer: I speak for myself not UC-Irvine**
 Senior Development Engineer
 Civil & Environmental Engineering
 UC Irvine
 E4130 EG,  Zot: 2175
 rkazanjy(--nospam--at)uci.edu

Lynn wrote:

> EphHirsch(--nospam--at)aol.com wrote:
>
> > 730 plf ?!!!  What are the hold-down forces on such a wall panel?
>
> Well, if the shear panel was 4 feet long, and 8 feet high, the uplift
> would be
> around 5,000 to 6,000 lbs.  An average sized hold down is all that is
> required.
>
> > And even if
> > a hold-down is found from a catalog (or special designed) to resist
> such a
> > force, what resists the hold-down itself? (That's probably a lot of
> concrete
> > footing dead weight required.)
>
> It does not take a lot of footing and slab to come up with 6,000 lbs.
>
> > The sill bolts figure to be pretty significant
> > too.
>
> Hmm, well 3/4" dia bolts at 16" o/c. in a 3x sill plate would probably
> work fine.
> No big deal.
>
> > Regrdless of what the code in question allows, such a force and
> nailing
> > pattern are pretty questionable, even if legal.
>
> Really!  Well, I can tell you it is very common.  In our office we do
> not use 3/8"
> plywood anymore, but a unit shear of 730 plf is very common.  I hope
> you were not
> thinking something like "KIPS" per lineal ft.  That would certainly be
> a problem.
>
> Lynn
>