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RE: Basement wall foundation

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An additional question is what is the intent of the current structure?  Do
they plan to build the apartments on top as originally designed?

The past 11 years has been a time of significant changes.  Accepting that
the garage was constructed in 1989, the UBC in force when it went to permit
could have been either the 85 UBC or the 88 UBC.  

I recall a design in Los Angeles that I worked on in 1989.  I had to update
a design done under the 85 UBC to the 89 UBC, and the changes were fairly
significant.  The changes from then till now are very significant,
especially if you compare the ACI 318-83 versus the ACI 318-99.

Even assuming the design was done properly per the 85 UBC and/or ACI 318-83,
the question of how it was constructed can only be answered by a very
concerted inspection effort (NDT and limited destructive testing).  You can
bring any existing structure into current code compliance, but not
necessarily economically.

The city's stance that they want a: " comparing the as-built garage
to the current code requirements although it will not require full
compliance with the current code." puts you right in the cross hairs.  At
first glance, it appears that the City is taking a degree of responsibility,
but they are not the "Professional".  Your report should clearly state all
code deficiencies and what the particular deficiency and the sum total of
all deficiencies mean regarding the intended performance.  That is not an
easy task.

Harold Sprague

> -----Original Message-----
> From:	Julian Chu [SMTP:julian(--nospam--at)]
> Sent:	Thursday, February 03, 2000 1:27 PM
> To:	seaint(--nospam--at)
> Subject:	Re: Basement wall foundation
> ----- Original Message -----
> From: "Charles Greenlaw" <cgreenlaw(--nospam--at)>
> To: <seaint(--nospam--at)>
> Sent: Wednesday, February 02, 2000 9:41 PM
> Subject: Re: Basement wall foundation
> > At 02:39 PM 02/02/2000 -0800, you wrote:
> > >We are evaluating an existing basement garage structure with concrete
> > decking built 11 years ago. The basement wall footing is 12" deep and
> 30"
> > wide. The walls are 9'-4" high 12" thick masonry block walls. All the
> > perimeter walls are also served as retaining walls. The original
> structural
> > details show only one continuous #5 rebar in the wall footings. Both the
> > owner and us are not comfortable with it.
> > >
> > >Can someone give us any retrofitting suggestion? It is a huge garage.
> The
> > perimeter wall length is around 5000 feet.
> >
> > ------------
> > What sort of unacceptable performance has occurred in the 11 years in
> this
> > footing? The purpose of the rebar is to prevent unwanted things from
> > happening. Perhaps nothing is acting on this footing that the single bar
> and
> > other helpful features of construction are unable to accommodate.
> >
> > Charles O. Greenlaw  SE   Sacramento CA
> This structure was originally designed to support three-story apartments
> on
> top of the deck. However, due to the econmic condition at that time, the
> ex-developer stopped the construction at the concrete deck. The building
> department wants to see report comparing the as-built garage to the
> current
> code requirements although it will not require full compliance with the
> current code.
> Someone suggests that we also look into the current ACI 318-99 section
> 21.8.
> We are also trying to find out what kind of technical/legal problems we
> will
> run into if there will be a lawsuit down the road.
> Regards,
> Julian Chu
> Newprt Beach, CA