Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

RE: Steel Seismic Design

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Charlie-

I believe the need for a 1997 AISC Seismic Provisions with Supplement
No. 1 is necessary for those of us designing OCBFs with the 1997 UBC (or
some variation therof). An alternative to publishing this variation of
the seismic provisions would be to recognize that we will be using this
code for a while (3 years +/-?) and to add to the language in Supplement
No. 2 that reads something like this:

"If the project falls within the jurisdiction of the 1997 UBC or some
variation thereof, OCBFs shall be limited to one story structures with a
weight less than 15 PSF."

Sorry for the public post (I know you asked for a private reply), but I
wanted to do this in case there was someone out there who was not aware
that the restrictions once put on OCBFs (most notably designing to 1.5
times the required strength) have gone away in Supplement No. 2 only
because the author(s) were anticipating their limited use in "state of
the art" codes (NEHRP, IBC, et. al.). Without this, there is a chance
that someone may read Supplement No. 2 and erroneously believe that,
somehow, the OCBF is actually "better" than the SCBF (see item 17 of
Supplement No. 2 which deletes Sections 14.2 through 14.5 of the Seismic
Provisions).

TIA,

Bill Allen, S.E. (CA #2607)

-----Original Message-----
From: Carter, Charlie [mailto:carter(--nospam--at)aisc.org] 
Sent: Wednesday, November 20, 2002 5:59 PM
To: 'seaint(--nospam--at)seaint.org'
Subject: RE: Steel Seismic Design


>Considering that the adoption of Supplement
>No. 2 will occur (way)before the adoption of
>the 2002 provisions, yes, it would be helpful. And,
>while you are at it, you should consider a "flavor"
>containing Supplement No. 1 only for those of us
>shackled with some variation of the 1997 UBC and
>want/need to use an OCBF in two stories (or more).

Thanks for the suggestion. Do you still have much call for 1997 AISC
Seismic Provisions with Supplement No. 1? If it is not extensive, I may
have to put that one off as staff time is dwindling. But let me know
(privately) if you think it is definitely needed.



>I HATE supplements and errata!

Yes, me too. I especially hate errata. They're in every document you and
I have ever used or produced, but I hate them all the same. Even more, I
hate them in AISC documents because they are ALWAYS something I should
have caught and didn't.

Charlie












******* ****** ******* ******** ******* ******* ******* ***
*   Read list FAQ at: http://www.seaint.org/list_FAQ.asp
* 
*   This email was sent to you via Structural Engineers 
*   Association of Southern California (SEAOSC) server. To 
*   subscribe (no fee) or UnSubscribe, please go to:
*
*   http://www.seaint.org/sealist1.asp
*
*   Questions to seaint-ad(--nospam--at)seaint.org. Remember, any email you 
*   send to the list is public domain and may be re-posted 
*   without your permission. Make sure you visit our web 
*   site at: http://www.seaint.org 
******* ****** ****** ****** ******* ****** ****** ******** 



******* ****** ******* ******** ******* ******* ******* ***
*   Read list FAQ at: http://www.seaint.org/list_FAQ.asp
* 
*   This email was sent to you via Structural Engineers 
*   Association of Southern California (SEAOSC) server. To 
*   subscribe (no fee) or UnSubscribe, please go to:
*
*   http://www.seaint.org/sealist1.asp
*
*   Questions to seaint-ad(--nospam--at)seaint.org. Remember, any email you 
*   send to the list is public domain and may be re-posted 
*   without your permission. Make sure you visit our web 
*   site at: http://www.seaint.org 
******* ****** ****** ****** ******* ****** ****** ********