Need a book? Engineering books recommendations...

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

Re: plan check ethics

[Subject Prev][Subject Next][Thread Prev][Thread Next]
This is an age old arguement. Contractors and architects who look at a
structure you have designed and says something to the effect that "I've
been doing this 20 years and I have never had to do it this way". My usual
response is "Well, after this one, you won't be able to say that". One of
the assumptions is that the adjacent wall was Code compliant. Another is
that the Code hasn't changed since the prior construction. While there are
several ways to prepare an engineering model of a structure, you would be
amazed how many structures are built without any engineeering basis (i.e.,
calculations) at all.

Another problem is that you may be using retaining wall software that does
not include the vertical component of the active earth pressure.
Conservatively, this vertical component would be equal to 1/3 of the
horizontal component located at the heel of the footing. Without this,
retaining wall footings become rediculously large. Check your input/output
and software algorithms.

Regards,
Bill Allen

----------
> From: Jeff Smith <smthengr(--nospam--at)sirius.com>
> To: seaoc(--nospam--at)seaoc.org
> Subject: Re: plan check ethics
> Date: Tuesday, August 19, 1997 10:33 AM
> 
> For small jobs, making arrangements for appealing a plan checkers ruling
> through the Board of Examiners, or the like, would delay the job and cost
> the engineer an even larger amount of time. Complaining to a plan
checkers
> superior can also label ther engineer as a trouble maker that could
result
> in future plan check overkill. 
> 
> Here is one of my experiences. I prepared structural drawings for a
repair
> of 25 LF of an existing 5 foot high concrete retaining wall located in a
> basement that was along the property line adjacent the city sidewalk. The
> existing wall was from 1919 and unreinforced but showed no signs of
> deflection or movement, but was cracked and spawled. I specified a new
> concrete wall and footing doweled in front of it, designed for 35 pcf.
The
> plan checker made me redesign the wall for 64 pcf  because it was not
back
> drained and I had to use 1000 psf bearing, .3 friction and 300 pcf
passive
> unless I had a soils report. The actual soil was a clayey rock. The
footing
> and reinforcing doubled in size and I had to place a 2'-6" deep key in
the
> footing that had to be jack hammered. When I came back to resubmit, the
> plan checker was on break and another structural plan checker took over.
> When he saw my design, he literally laughed at the over design and
stamped
> it approved, with no further plan check. This ended up costing the Owner
a
> lot of money. 
> 
> Since then I have had several other plan checks by the same engineer. 
> Regards,
> 
> Jeff Smith. S.E.
> phone: (415) 543-8651
> fax: (415) 543-8679
> email: smthengr(--nospam--at)sirius.com
> 
> Smith Engineering
> 27 South Park
> San Francisco, CA 94107
> 
> 
>