Need a book? Engineering books recommendations...

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

Re: Architect cheating on structural calculations - where's the building depa...

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Antonio: 

I understand your fraustration about the rigid/flexible diaphragm because that goes against the general practice.  However, the code is pretty specific about what flexible diaphragm is.  Unless you can prove that the diaphragm is flexible by calc, I think the plan checker is correct in asking you to provide rigid diapphragm calcs.  (Some of the cities now provide an alternative to rigid diaphragm analysis by using the simplified base shear.)   

You indicated "My biggest gripe in general is that one or two story residences are seismically treated (plan checked) like major structures".  My attitude has been that the earthquake does not know if you structure is  major or minor.   It will find the weakest link and create havoc if the link is weak enough. ( My understanding is that of the total damage in the Northridge earthquake, half the dollar amount was due to damage to single family homes.)   Also from the point of view of the client, that single family home is his "Taj Mahal" and a major structure.

Gautam


>>> ASLCSE(--nospam--at)aol.com 12/09/05 10:08AM >>>
In a message dated 12/8/2005 6:21:18 PM Pacific Standard Time, jkestner(--nospam--at)somervilleinc.com writes:

We have seen all kinds of plan checks over the years:

One plan checker reviewed our drawings and thought all the beams were undersized. He even had reams of output from computer programs that told us the beams were undersized. He wrote this up in a letter to us and the Owner. It turned out that this plan checker was not an engineer. He used to be a structural steel detailer and thought that he knew how to design beams. 

Other plan reviews come back often with no comments.

Jim K.


I too have seen all kinds of plan checks over the years, but I must say, with the vast majority of them I have no gripes in regard to structural corrections. My biggest gripe in general is that one or two story residences are seismically treated (plan checked) like major structures. In most cases, having to analyze the residence with a flexible diaphragm and as a rigid diaphragm is IMO an overkill.
What I really hate is a preprinted correction sheet where the plan checker can circle what ever comes close to his question, but does not address what he or she really wants to know. Of course, this kind of correction list makes it easier for the ones who still have  problems expressing themselves in English (and there are quite a few of them!).  
How I answer the plan check corrections can also depend on my mood, sometimes with a smile, other times I am sarcastic. Well, everybody is human!!
Question: How do you fellow engineers "rate" the Building Departments of Santa Monica and Malibu??
My 2 cents.
Antonio S. Luisoni, SE


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