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RE: ACI 355.2 - issue - THE BIGGER QUESTION ON CODE CREATION

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So how does something like this get so far out of hand before it makes it to
the attention of the professional community. This is not much different than
the problems most of face OVER-designing to inflated standards for wood
construction that were codified before practical engineers knew what hit
them.
It is going to be easy to accuse engineers who are in private practice for
allowing this to happen by not reviewing and responding to model drafts of
codes. However, the sad fact is that the code creation process is not
limited to one committee doing one set of tasks that can have an affect on
the way we work. Some of the specific problems include;
1. Identifying all of the groups who are contributing to the codes and
seeking out the work that they are doing.
2. Obtaining drafts of the work before it is near completion and ready for
final review. In most cases, the professional community will not see any of
the work until it is "ready for publication" at which time it is generally
too late to make any but administrative changes to the rhetoric. This is
done purposely to prevent too much intervention from outside sources.
Let me ask you this - there is a movement to create Multi-tiered licensing
that has been discussed publicly both in Structural Engineer Magazine, one
the Structuralist.Net discussion forum and right here on this Listservice.
Since bringing the issue to attention and raising criticism on various
levels, subsequent work has literally vanished from availability to any
individual or group who might be interested in participating. The same
problem exists in other code related issues which are pushed back on the
practicing engineer for failure to act when the information is conveniently
concealed until it is too late.
3.There are many groups currently doing work on wood structures - CUREe,
NIST, NAHB, AF&PA, AWC, CWC, etc. etc. etc. and in each case there may be
work available but do you know how to find it.

The Structuralist.Net is trying to filter these sources and present a
Webpage where model drafts of potential codes can be linked or posted for
review and comment. All we wish to do is to reduce the individual engineers
time and frustration seeking the sources of this information.

When FEMA 273 was under development, how many knew that the draft was
available on the Degenkolb Website and not on the FEMA website? It wasn't
until Frank McClure disclosed the source of these documents to the
listservice that we had the opportunity to review them - over a year after
they were released.

We have a problem and the ACI355.2 issue is only the tip of the iceberg as
most of us did not know of this problem until it was brought to our
attention by this group of manufacturers. How much more is out there that we
have no control over.

It appears that we can expect the same type of ambiguity that occurred in
the 97 UBC to occur in other codes as the process grows more complicated and
organizations fight for control as we are currently seeing in the ICC verses
NFPA argument published in this months NCSEA Structures Magazine.

Good luck in getting a decent code that satisfies the ability to adequately
protect the public and to do so economically.

Dennis S. Wish, PE

-----Original Message-----
From: Peter Higgins [mailto:76573.2107(--nospam--at)compuserve.com]
Sent: Wednesday, March 14, 2001 5:47 PM
To: INTERNET:seaint(--nospam--at)seaint.org
Subject: Fw: ACI 355.2 - Proposed Test Criteria for Post-Installed
Anchors


As one who specifies literally tens of thousands of these each year, I must
agree that ACI is fixing something that isn't broken.

Expansion anchors have performed extremely well for decades, and in
numerous earthquakes (where they ripped apart a slab in one failure after
the shelving structure failed and put them into extreme tension).

If expansion anchors had a fundamental problem, we would have known long
before now as these anchors would have pulled up all over the place in past
earthquakes. It simply hasn't happened.

The point of the revised testing is theoretically sound, and the test
protocol of artificially creating a crack and installing the anchor into it
is intuitively attractive. However, the protocol then completely ignores
the mass restraint present in the typical slab by taking off all
confinement forces before testing for tension. This is neither
theoretically or practically correct as has been proven many times in the
past.

Clearly, any anchor requiring any side reactions from the hole will fail
this test, leaving only undercut anchors available to resist tension. If
this is the case, we'd better remove all our expansion and expoxy anchors
from existing slabs. Per ACI 355, this should be a cinch. Try prying even
one of these well set anchors from any slab of any age, see how easy it is
and then decide if Murphy isn't correct once again: Don't fix it if it
ain't broke.

This is simple, practical engineering, and completely ignores the lawsuit
issue which may or may not have merit. However, one must question the
outlawing of well established materials with known performance records.
When that happens, it is usually the theory that is wrong, no matter how
attractive and intuitive it may seem.

Peter Higgins, SE