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RE: structures & ethics

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You've got a good real-world problem/situation here.
 
Steve, I believe that in having been hired to investigate the structure for your client, you would be reporting that the structure is not code compliant, and then pointing out those areas in which you have determined it does not meet code. Even if it met the code in the year under which it was built (a situation I run into more often), it may not be compliant with current code. Codes evolve for good reason (e.g. drywall gypsum board shear walls). I would point those differences out in the report, as it is needed for the client to make the decision. Ultimately it becomes an issue between the owner of the building, who has liability for the tenants, and the enforcement agency, who has jurisdiction over the building standards in the community. Once the owner/client is aware of the hazards, we can move to discussing hazard mitigation.
 
Regarding the perceived oddity of the material overstresses in your calculations versus the actual 30 year performance of the building, I generally agree with the remarks that have been stated so far in this discussion thread. Namely, adjacent materials and conditions may be providing stress redistributions, and design load assumptions may be greater than actually applied. One in particular that I did not see fully mentioned is the variance in material ultimate strength. One response mentioned sample testing. By virtue of it being a natural material, the deviation of actual ultimate strength as obtained by testing from the expected strength (even is select structural grades) will be significant. Also, design strength specifications are based on expected average moisture content and if the structure has provided an environment in which the wood moisture content is less than that, you will see greater ultimate strengths. The drier conditions could result either from climate location, or from conditioned space (heating).
 
These are just quick opinions based on what I browsed so far on this discussion thread. Good luck.
 
Best,
Thomas Honles, SE, PE
Los Angeles, CA
 
-----Original Message-----
From: S. Gordin [mailto:mailbox(--nospam--at)sgeconsulting.com]
Sent: Monday, November 22, 2004 11:33 AM
To: seaint(--nospam--at)seaint.org
Subject: Re: structures & ethics

Gautam,
 
I hope I did not mentioned anywhere that the building is, or was supposed to, "come tumbling down."  I do not believe in that happening.  The building survived at least two good-size earthquakes (1971 and 1994), and is not going anywhere any time soon.  After all, the safety factors in wood design are in the order of 4-to-6, which, obvioulsy, quite safely covers the noted overstress.   
 
My problem is - can we allow the building to stand without strengthening, even in the "repaired to preexisting" condition, while knowing that it is not code-compliant?
 
Example: based upon my observation, I would assume that the building had not been re-roofed.   What will happen when the reroofing start?  Probably, nothing.  But at a 12' height, something may happen.  Then what?
 
I do not really care what my client would THINK about my degree.  I do care about what he will be willing to DO about my license in case of any problem - no matter how much he wants to save money now.        
 
Along with my professional and personal ethical considerations, this is my main concern. 
 
Thanks,
 
V. Steve Gordin, PhD
Registered Structural Engineer
Irvine CA
 
 
 
----- Original Message -----
Sent: Monday, November 22, 2004 10:58 AM
Subject: Re: structures & ethics

Steve:

Since the building has been standing up for the last thirty years in
spite of the 70-100% overstress for DL +LL and 15%  for DL,  I would
guess it will stand another 30 years without any problem (you did not
say that the members were sagging & assumming no major earthquak hits
it).   Either the loading is being overestimated or the strength
underestimated.