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RE: storage racks with partially restrained moment connections - wind frame analysis in high seismic zones

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The problem is that if the facility is existing, and racks are moved,
removed, or replaced; a building permit may or may not be required.
Southern California municipalities might require inspection, but how is this
triggered, and documented for existing construction?  It is an easy trigger
for new construction, but the existing construction trigger is not clear to
me in the UBC or in the Blue Book.

The 1997 RMI recently upgraded their seismic design standard, but it still
needs to be updated to reflect the 1997 NEHRP mapping.  The issue on how to
enforce and monitor is still there and should be more uniform for all of the
IBC territory.  The new mapping contained in the NEHRP and IBC also need a
bridge, because the RMI has yet to pick up on the 1997 NEHRP maps.  The RMI
uses the old Av and Aa maps.  The UBC is linked to the old zones.  There
will be many racks being designed and built today that will be inadequate
when the IBC kicks in (which is a whole different issue).  The standards
need to be uniform for the NEHRP and IBC, and not reliant on local

The 1997 UBC contains 3 pages of requirements on steel storage racks and is
based on the 1990 RMI.  The 1997 RMI contains 28 pages of requirements and
38 pages of commentary.  The "back bone" of the SEAOC Bluebook and the 1997
UBC was the 1990 RMI and required a total rewrite by the primary author Dr.
Victor Azzi for the 1997 RMI.

I would be interested in the exact wording of these regulations.  You are
with the City of Palmdale.  I would love to see your regulations.  I could
put the same charging language in the NEHRP and require the "jurisdiction
having authority" to require design and inspection and appropriate placards.

The engineer who helped author the requirements in the SEAOC Blue Book and
the 1997 UBC also sees the ambiguities.  He is also a colleague on BSSC
Technical Subcommittee 13. 

Does Palmdale require seismic ratings on the placards on the rack?  
Does Palmdale require sealed structural drawings and calcs to be maintained
on site?  
Is the 1997 RMI referenced or required by Palmdale?  
What does Palmdale do for modifications to racks in existing buildings?  
How are the building official reviews triggered for modifications to
existing racks?
What is Mr. Sal's phone number and address?

This is an issue for the 2003 cycle of the BSSC Technical Subcommittee 13,
and is by no means resolved.  Any help is welcomed.  If these issues are all
resolved, I'll quit screwing around and go fishing.

What do the other Southern California jurisdictions do?  Any other building
officials out there today?

Harold O. Sprague TS13 Chair 1994-2000

> -----Original Message-----
> From:	Sid Danandeh [SMTP:sdanandeh(--nospam--at)]
> Sent:	Monday, March 19, 2001 12:10 PM
> To:	'seaint(--nospam--at)'
> Subject:	RE: storage racks with partially restrained moment
> connections - wind frame analysis in high seismic zones
> well 
> In Southern California where I have worked for the past 20 years! Racks
> are
> plan checked and also inspected by the building depts.
> Code allows the building official certain latitude if racks are less than
> 8
> feet tall. But if racks are taller than 8 feet most cities that I have
> worked for required structural engineering calculations.
> There are couple of companies in Southern Ca that mostly perform rack
> designs one is called SEISMIC and its director Mr. Sal. He is very active
> in
> various committees. There are other rack design firms in Glendale etc.
> The racks have their own base shear formula in the 1998 CA code. The rack
> foundation is also analyzed using beams on elastic foundation, or a
> simplified method by Eugene Birnbaum is very poplar to deign footing for
> racks. This method was accepted by LA County in 1986.
> You are right Fire dept.'s also inspect racks . But they are interested in
> the so called  IN Rack sprinklers and high piled storage provisions. For
> the
> definition if the rack is more than 12 feet high its classified as high
> plied storage. High piled storage requirements kick in certain fire safety
> requirements for the building.
> We have been basically using the SEAOC's blue book that was used a as the
> back bone for UBC's structural provisions for years and years. We were to
> use some more NEHERP provisions this year using the 2000 IBC , but IBC was
> not adopted in California. The UBC and the SEAOC blue book are very clear
> on
> their requirements for  design and inspection of racks and most major
> metropolitan cities in Southern California that I know of adhere to these
> requirements.
> -----Original Message-----
> From: Sprague, Harold O. [mailto:SpragueHO(--nospam--at)]
> Sent: Saturday, March 17, 2001 10:43 AM
> To: 'seaint(--nospam--at)'
> Subject: RE: storage racks with partially restrained moment connections
> - wind frame analysis in high seismic zones
> As a member of the BSSC TS 13, storage racks fall in my chapter of the
> NEHRP.  This area has been a cause of concern and study.  But even more
> fundamental to structural theory is how racks are used and approved.
> Anyone
> can take a rack originally designed and built for Dallas and assemble it
> in
> the San Francisco area.  The inspection is a crap shoot.  If anything, the
> fire marshal might inspect it to see if the racks are loaded within the
> posted rating.  But whether or not the rack is in the appropriate Seismic
> Design Category is neither generally posted nor generally checked.
> This is an area that requires further study and work by the RMI and TS 13.
> Regards,
> Harold O. Sprague