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RE: Effect of anchor bolts sleeve

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I would have said six diameters, but I'd go with your rule of thumb or make
them use a bearing plate as per the AISC detail.  (I doubt that they can
show you an industry standard that supports their view...)  The problem is
that the sleeve effectively prevents any load transfer between the grout and
the hole wall.  The head diameter of a 7/8" std hex bolt is about 1-1/4",
and the bearing stress at failure will be about 12f'c for a 6" embedment.
Their detail effectively creates an anchor with a 2" embedment.  That should
be justification enough.

Regards,  John Silva
> ----------
> From: 	Sherman, William[SMTP:ShermanWC(--nospam--at)cdm.com]
> Reply To: 	seaint(--nospam--at)seaint.org
> Sent: 	Monday, November 15, 1999 2:34 PM
> To: 	'seaint(--nospam--at)seaint.org'
> Subject: 	RE: Effect of anchor bolts sleeve
> 
> The contractor has shown a 7/8" diameter anchor bolt with a 6-inch
> embedment
> (per UBC anchor bolt table) and using a 2-inch diameter standard steel
> pipe
> sleeve by 4" long, to be filled with grout after the equipment base plate
> is
> set.  Thus the sleeve would be within 2-inches of the bolt bearing.  
> 
> I have generally used a rule of thumb that the sleeve should not be longer
> than 1/2 the embedment depth.  I have seen a project-specific criteria
> that
> limits the sleeve to no closer than 4 bolt diameters from the bolt bearing
> surface.  But I have not seen any industry standards which address this,
> and
> the contractor wants justification that their detail is inadequate.  
> 
> > -----Original Message-----
> > From: Silva John (sj) [mailto:Silva(--nospam--at)hilti.com]
> > Sent: Monday, November 15, 1999 12:15 PM
> > To: 'seaint(--nospam--at)seaint.org'
> > Subject: RE: Effect of anchor bolts sleeve
> > 
> > 
> > That's a good point, William.  I am not aware of any direct 
> > research on
> > this.  Will the sleeve be grouted?  What are the bolt and 
> > sleeve diameters?
> > 
> > If you want a quick answer, I'd say provide a larger bearing 
> > surface by
> > using a plate washer  (AISC shows this detail in Engineering for Steel
> > Construction).
> > 
> > Regards,
> > 
> > 
> > J. Silva, SE
> > Hilti, Inc.
> > silva(--nospam--at)hilti.com
> > 
> > 
> > > ----------
> > > From: 	Sherman, William[SMTP:ShermanWC(--nospam--at)cdm.com]
> > > Reply To: 	seaint(--nospam--at)seaint.org
> > > Sent: 	Monday, November 15, 1999 8:51 AM
> > > To: 	SeaInt Listserver (E-mail)
> > > Subject: 	Effect of anchor bolts sleeve
> > > 
> > > Is anyone aware of any research or publications which 
> > address the effects
> > > of
> > > embedded steel sleeves on the pullout strength of steel 
> > anchor bolts?  If
> > > the sleeve becomes too close to the embedded head, it seems 
> > that it would
> > > affect the bearing at the head and overall pullout cone.  I 
> > do not see
> > > this
> > > addressed in ACI 349, although one of the diagrams shows an 
> > "optional
> > > steel
> > > or PVC sleeve".  (A contractor has submitted an equipment 
> > anchor bolt
> > > detail
> > > which has a 6-inch embedment and a 4-inch deep steel sleeve.)  
> 
>