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RE: Filigree Wideslab

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Jim,

My first exposure to a Filigree job was as a peer reviewer back in 1982.  I
asked Chicago (the evil twin) to send me some information.  They did.  In
the experience literature one of the "successful" projects listed was the
one I was consulting on.  They had not even broken ground.  

Of particular concern were the spandrel beams supporting 60 ft span slabs
for a parking garage.  They were wide and thin with normal size square
columns.  I was concerned about how they made torsion work in the spandrels.
When asked, I was told not to worry, and that there was another garage just
like it in Philadelphia.  

I called the PCA representative in Philadelphia (which PCA had back then) to
look at it and give me his general impressions.  He did and replied that he
did not know what I was looking for, but there were torsion cracks
everywhere.  I conveyed what I had learned to the EOR.  The EOR was
extremely grateful.  When we received the drawings back after revision, the
garage was changed to a one way post tensioned structure.

That said, the office building adjacent to the garage was fine structurally.
I did not learn about the lack of a UL stamp until about my 4th or 5th
Filigree project.  The only company that can put a UL stamp on their panels
is Mid-States (the good Filigree guys).

Good luck!

Regards,
Harold O. Sprague

> -----Original Message-----
> From:	frp 2000 [SMTP:frp2000(--nospam--at)hotmail.com]
> Sent:	Wednesday, November 15, 2000 10:00 PM
> To:	seaint(--nospam--at)seaint.org
> Subject:	Re: Filigree Wideslab
> 
> Harold,
> 
> Well, now there might be TWO of us who won't sleep nights.
> 
> The underlying reason for my initial post was that I have been asked to
> check the feasibility of strengthening an existing "2-1/4 Filigree
> Wideslab"
> that has been "damaged" and is in need of repair. Naturally, the extent of
> the damage must first be verified.
> 
> However, your comments lead me to believe I must be concerned about  the
> original design and installation of the slab even without any subsequent
> damage.
> 
> The slab spans 41 ft and is 8ft wide and 12 in deep. The objective is to
> supplement the existing flexural reinforcement on the underside of the
> slab
> with 72 ft-kips of additional moment capacity.
> 
> jim
> 
> 
> ----- Original Message -----
> From: "Sprague, Harold O." <SpragueHO(--nospam--at)bv.com>
> To: <seaint(--nospam--at)seaint.org>
> Sent: Wednesday, November 15, 2000 6:23 PM
> Subject: RE: Filigree Wideslab
> 
> 
> > Jim,
> >
> > I had extensive dealings with Filigree and wake up in the middle of the
> > night in terror.  Those dreams have become less frequent over the years.
> > Now, after your post,  I am back to therapy.
> >
> > Seriously I saw that you already got the web site to Mid-States
> Filigree.
> > They are the good guys.  They know the theory,  they have the practice,
> and
> > they know what they are doing right down to the details.  I did about 6
> or
> 8
> > buildings with the evil twin.
> >
> > The spin off that went to Chicago and then to Kansas City were the
> outlaws.
> > They never got the patent rights held by Mid States so that UL
> assemblies
> > done with them are not enforceable.  There are several buildings in
> Kansas
> > City, St. Louis, Philadelphia, Chicago, Topeka, etc. that were done with
> the
> > outlaw brand of Filigree.  The group had a couple of different names
> with
> > Filigree included.  The outlaw was purchased and then dropped by a
> precaster
> > first in Chicago and then in Kansas City.  They had a tendency to not
> pay
> > their bills.
> >
> > The basic method is sound (using precast and cast in place to form
> composite
> > reinforced concrete), and in the hands of qualified engineers the
> finished
> > structure was sound.  A few of the technical staff in outlaw Filigree
> were
> > very good, but the sales pushers were way over their head.
> >
> > I could tell you horror stories.  But they are too gruesome for this
> list.
> > If you are going to use Filigree, take the high road, go with
> Mid-States,
> > and have pleasant dreams.
> >
> > Regards,
> > Harold O. Sprague
> >
> > > -----Original Message-----
> > > From: frp 2000 [SMTP:frp2000(--nospam--at)hotmail.com]
> > > Sent: Wednesday, November 15, 2000 7:01 PM
> > > To: seaint(--nospam--at)seaint.org
> > > Subject: Filigree Wideslab
> > >
> > > Does anyone on the List know of  references that cover the design and
> > > analysis of "filigree" slabs??
> > >
> > > They are voided slabs that have been used in the past in the Chicago
> area.
> > >
> > > Any assistance is greatly appreciated.
> > >
> > > jim korff, pe
> > >
> >
> >
>