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RE: Hardy Frames

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This is good news as I tried to get the city of La Quinta to accept the
Hardy panel as an alternate braced panel and their typical HFx48 for
replacement of braced panels. Although this is not our responsibility as
these are prescriptive methods, the braced panels called out in the code
don't require resistance to uplift unless they are less than a 2:1 ratio
and they can be installed in interior braced walls (where the span
exceeds 50') but there is no provision for a thickened slab or
foundation which means that the Holddown and anchor bolts end up in the
dirt below the slab.

You would think that the code writers for conventional construction
(2320) would figure out that you can't install anchors into soil without
them rotting away. The worst part is that local inspectors and
non-engineer plan checkers approve these because it is published in the
code. When challenged, I have been denied upgrades because the plan
checker did not know what the affect would be on the structure and
wanted to stick to the letter of the code. I was doing this for a
non-profit organization that I was volunteering my time for and the
Hardy was donating their frames to the project. The upgrade would have
made the homes perform better so to get around this code restriction, we
designed the braced panels as the code required and installed the Hardy
frames during construction. As long as the Conventional provisions were
honored, the city had no problem with adding additional shearwalls.

This year I am not involved and Simpson is donating their "Strong-Walls"
for this non-profit project that teaches high school students to build
homes and they construct three to four homes per school year. The
quality of construction in my professional opinion is outstanding and
much of this comes from the support of companies like Simpson and Mitek
(Hardy).

I've left the project after being on the board for five years due to a
dispute with the president of the board of directors who was more
interested in completing the homes on time than the quality of what the
students were building. He worked for a large tract housing company and
had no conception or belief in engineering. It ended up training
students to do it right so they could get jobs with company's like this
who will push them to do it wrong in the field.

Regards,
Dennis

-----Original Message-----
From: Suresh Acharya [mailto:struct(--nospam--at)att.net] 
Sent: Thursday, October 23, 2003 8:36 PM
To: seaint(--nospam--at)seaint.org
Subject: Re: Hardy Frames

Hi Bill,
I would suggest paying attention to the footnotes in the ICBO report - 
sill plate thickness issue, etc. If you mix and match Hardy Frame with 
the wood shear walls, the report requires you to distribute the shear 
based on their stiffnesses.

A note:
Hardy Frames have been widely misused, particularly in the remodel 
projects where footings on which these frames are installed are ususlly 
not capable of carrying the huge compression and uplift forces. Now 
thanks to the new ICBO report, a slender Hardy Frame is allowed to use 
as a braced panel in the Conventional Construction UBC 2320).  I think 
this defeats the original intent of the conventional construction 
provisions.

Suresh Acharya, S.E.


Bill Allen wrote:

>I am looking for advice from those who have used Hardy frames in
>residential construction in high seismic zones (particularly in CA with
>the 1997 UBC / 2001 CBC).
>
>I've seen the literature, scanned the ICBO report, but, frankly, I
don't
>pay attention to things very well until I have to use it on one of my
>projects. Well, I did a stoopid thing and mentioned Hardy frames to a
>client of mine and he would like to substitute all double sided shear
>walls with Hardy frames.
>
>For those of you who have used them, any pitfalls? Anything to watch
out
>for? Any change in the analysis? To me, they look like OCBFs requiring
a
>different R, requiring multiplying design forces by 1.5 (or worse,
>limited applicability due to AISC Seismic Provisions), etc. but
possibly
>the ICBO report has avoided all of this.
>
>Input would be most appreciated.
>
>Regards,
>
>T. William (Bill) Allen, S.E. (CA #2607)
>V/F (949) 248-8588
>San Juan Capistrano, CA
>http://members.cox.net/ballense/
>
>
>
>
>
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