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

RE: Wind Loading on Existing Structures

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Wouldn't that also hold true for seismic events?  :<)  

The rationale behind lower loadings due to infrequent events and existing
buildings is really just a question of risk of exposure (an existing
building has an assumed shorter remaining economic life and hence a lower
probability that the building occupants will experience the infrequent event
during the remaining life of the building), not what the maximum (or more
appropriately, design maximum) event is.

Bill Cain, SE
Oakland CA

	-----Original Message-----
	From:	Charlie Carter [SMTP:carter(--nospam--at)]
	Sent:	Friday, September 29, 2000 7:10 AM
	To:	'seaint(--nospam--at)'
	Subject:	RE: Wind Loading on Existing Structures

	I don't think there is any provision for reduced wind loads when
examining existing buildings. If there were, I'd ask how the wind is
supposed to know that the building was an existing building, not a new one?
	However, the fact that your existing building withstood the high
winds you described (I took that to mean higher than the original design
winds) probably means that there is more strength in the structure than
assumed in the original design. Instead of trying to tweak the wind load
side of the equation, can you work on the strength side to more accruately
reflect what is happening when higher winds hit the building?
	-----Original Message-----
	From: T. Eric Gillham PE [mailto:gk2(--nospam--at)]
	Sent: Thursday, September 28, 2000 7:29 PM
	To: seaoc list
	Subject: Wind Loading on Existing Structures

		Listserver Members:
		Does anyone on the list have any experience with Code
required wind loading on existing structures?  In particular, I am
interested in knowing if there are any codes that promulgate a lesser wind
loading requirement on existing structures, as compared to new structures,
along the lines of NEHRP, ATC or other codes with regard to seismic.
		Currently, I have a project that involves a 30+ year old
metal warehouse structure that is being checked for code compliance for our
155mph design wind speed.  This structure has been through 4 major typhoons
with recorded wind speeds exceeding 155mph sustained.  Based upon this, and
the current condition of the structure (it has weathered the years, no pun
intended, quite well with minimal if any signs of corrosion), it would
appear that MAJOR retrofitting would be overkill, although there are some
areas that need to be addressed regardless of what requirements I adhere to.

		Any suggestions would be welcome.
		T. Eric R. Gillham PE
		PO Box 3207 Agana Guam 96932
		Ph: (671) 477-9224
		Fax: (671) 477-3456
		Pgr: 720-8891
		gk2(--nospam--at) <mailto:gk2(--nospam--at)> 

******* ****** ******* ******** ******* ******* ******* *** 
*   Read list FAQ at: 
*   This email was sent to you via Structural Engineers 
*   Association of Southern California (SEAOSC) server. To 
*   subscribe (no fee) to the list, send email to 
*   admin(--nospam--at) and in the body of the message type 
*   "join seaint" (no quotes). To Unsubscribe, send email 
*   to admin(--nospam--at) and in the body of the message 
*   type "leave seaint" (no quotes). For questions, send 
*   email to seaint-ad(--nospam--at) 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: 
******* ****** ****** ****** ******* ****** ****** ********