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RE: New LFRD/ASD Steel Code (Was: Any Young Engineers Out There?)

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Bill,

I am not of such a different view point...it is more a matter of I really
don't know how it would play out as I am not a lawyer.  You are correct
that there is an arguement in the form of "standard of care" or intent of
the code committee members is that WSD is still permitted.  But, I really
don't know if that arguement would fly in the "legal world" (i.e. court)
or not.  I agree that in many ways it is a reasonable arguement.  I also
believe that there is a reasonable arguement as to why it should not be
permitted.  That would be that the WSD method that is the old Appendix A
has largely be neglected since before I graduated and does not represent
the sum total level of knowledge that is present in the Strength method
that is in the main body of the code.  Thus, someone could reasonable
argue that the old Appendix A does NOT really represent a level equal to
the "standard of care".  This is not a "knock" against WSD, but rather an
acknowledgement that it has not really kept pace with SD.  Thus, someone
could argue that doing WSD would be fine if all the knowledge and
improvements that are present in SD were put into WSD...much like what
AISC has done with ASD and LRFD in the 2005 spec.

Overall, it is not much of an issue as I believe many of the "holdouts"
for WSD work in the world of water tanks or environmental structures and
as such they do have a perfectly legal document (assuming it gets adopted
by reference by local jurisidictions) that still permits WSD...ACI 350.

Regards,

Scott
Adrian, MI


On Tue, 24 Jan 2006, Sherman, William wrote:

> I agree with most of what Scott has written below, but I have a little
> different viewpoint regarding the "legality" of using working stress
> design (WSD) for concrete design.  I do agree that technically the
> Commentary is not part of the legal document, so disagreements on its
> use are quite possible.  But I also feel that a reasonable argument can
> be made that the same ACI committee members that wrote the code
> provisions also wrote the commentary to the code.  Thus the commentary
> does represent their "intent", even if the code is not so clear.  It
> would seem that using WSD per the 1999 methods would still meet the
> "standard of care".
>
> As suggested by Scott, ACI 350 has retained the Alternate Design Method
> in an Appendix, including in the 2006 version of the ACI 350 code soon
> to be published.
>
>
> William C. Sherman, PE
> (Bill Sherman)
> CDM, Denver, CO
> Phone: 303-298-1311
> Fax: 303-293-8236
> email: shermanwc(--nospam--at)cdm.com
>
> -----Original Message-----
> From: Scott Maxwell [mailto:smaxwell(--nospam--at)engin.umich.edu]
> Sent: Tuesday, January 24, 2006 3:53 PM
> To: seaint(--nospam--at)seaint.org
> Subject: RE: Any Young Engineers Out There?
>
> Bill,
>
> I doubt that you will see such in this case.  In the case of concrete
> design (ACI 318), they were really trying to make working stress the
> bastard, step child of concrete design if not eliminate it.  And while
> they may have wanted it to go "bye-bye", working stress was still a
> perfectly "legal" and acceptable alternative as it was put into a
> perfectly "legal" (from the point of view of whether you could use it or
> not) form in an appendix...that is until the ACI 318-02, which got rid
> of the working stress (aka alternative design) appendix.
>
> Now, the commentray of ACI 318-02 in section R1.1 does state: "The
> Alternative Design Method of the 1999 code may be used in place of
> applicable sections for the 2002 code."  Now, while I am not lawyer
> (which if true would likely make you dislike me more than just our
> differences of political views), I believe this statement in the
> commentary has about as much "force" (i.e. legally applicable) as if I
> told you it was perfectly legal for you to drive 150 mph in a 55 mph
> zone.  Commentarys are non-mandatory documents and thus are _NOT_ part
> of the code.  As such, a code official in a jurisdiction that uses the
> 2003 IBC (and thus the ACI 318-02) would be perfectly within his/her
> right to not permit someone to use the Alternative Design Method for a
> building.  I will note, however, that I believe that ACI 350 (the "water
> tank" code) does still have provisions in it for "working stress"
> design...thus, there are technically situations where working stress
> could "legally" be done.
>
> Now, the situation will be different in steel.  ASD is _NOT_ being
> eliminated or even reduced to a bastard, step child.  AISC tried to do
> that (so to speak) and lost the battle.  They have "surrendered" and ASD
> will live (and does live in 2005 spec).  But, it will no longer be our
> "parent's" ASD, so to speak.  We get a nice updated version that is
> virtually no different from the LRFD "flavor" at least on the capacity
> side of the equation.   And I highly doubt that there will be "wording"
> in the model building codes that allow the use of "older" ASD specs.
>
> To reinforce that last point, in general when the NDS updates the wood
> code (ASD) or ACI updates the strength method of concrete design (with
> the major exception of the change in load factors and going to the
> Unified Design Method in the main body of the code...both of which are
> not really the same situation as what I am talking about), do you see
> provisions in the model building codes (or the material standards
> themselves) that say "if you don't like the changes that we made to
> these methods, feel free to just ignore them and keep using what you
> have been using"?  The point is that steel ASD as a method is not being
> eliminated (or "diminished")...it will still be there, but they updated
> it.  As such, I highly doubt that there will be an "out" that will allow
> use of the "old" ASD spec.
>
> Now, how well code officials/jurisdictions will enforce the use of the
> new ASD specs remains to be seen.  I have no doubt that there will be
> plenty of jurisdictions where they will not enforce the use of the spec
> let alone even know what the differences actually are.
>
> Regards,
>
> Scott
> Adrian, MI
>
>
> On Tue, 24 Jan 2006, Polhemus, Bill wrote:
>
> > BUT...
> >
> > Expect to see wording in the codes allowing use of the "older" ASD
> > method, much as ACI 318 carried "working stress" design of concrete in
>
> > an appendix for a very long time.
> >
> > Remember that codes are consensus documents. For "consensus" read
> > "political."
>
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