Need a book? Engineering books recommendations...

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

RE: OMF Connection Design

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Matt:

My opinion is that the panel zone is part of the connection and needs to
be designed to be at least as strong as 1.1*Ry*Mp, but will yield to
superior wisdom.

Respectfully,
Scott Haan P.E.
Deputy Building Official

-----Original Message-----
From: Hood, Matthew O. 
Sent: Tuesday, June 29, 2004 12:40 PM
To: seaint(--nospam--at)seaint.org
Subject: OMF Connection Design



I am currently plan checking the connections of an OMF in a
Pre-engineered metal building. I have indicated to the Engineer that the
connections need to be designed in accordance with the '97 AISC seismic
provisions so that they resist a moment equal to 1.1*Ry*Mp of the beam
or the maximum moment that can be delivered by the system. The Engineer
has indicated that the maximum moment that can be delivered by the
system is governed by the panel zone shear strength of the column. The
Engineer cites the commentary to FEMA 350 section 3.2.1 as justification
where it states: "for Ordinary Moment Frame systems, fully restrained
connections that permit development of plastic hinges at locations other
than within the beam span, e.g. in the panel zone or in the column, are
permitted."

It is the opinion of my office that the panel zone is interior to the
connection and should, itself, be designed for the maximum moment, not
determine the maximum moment. Meaning that something else (e.g. Lateral
torsional buckling of the beam) should be the failure mode used to
determine the maximum moment. The panel zone should then be designed to
resist those forces. I'm reading FEMA 350 section 3.3.3.2 and section
3.6.1.1 specific to bolted end plate connections which says: "The
connection shall be designed so that yielding occurs either as a
combination of beam flexure and panel zone yielding or as beam flexure
alone."

Any thoughts/opinions?

-Matt



******* ****** ******* ******** ******* ******* ******* ***
*   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
******* ****** ****** ****** ******* ****** ****** ********