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

RE: Old Concrete Repair Question

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Ron,

In the 1950's they used Working Stress Design.  I would use the ACI 318-63
(its the oldest ACI 318 that I have).  I would also use Singleton's Manual
of Structural Design which is based on the ACI 318-1940 and the work of
Taylor, Thompson & Smulski.  The amount of reinforcing steel varied with the
material strengths, but varied from a low of 0.23% to a maximum of 2.98%
according to my dusty, old Rectangular Beam tables.  Be careful on the
determination of strength.  Compression steel in beams was often used in the
1950's.

Check out the NAVFAC MO-102.10, Concrete Crack and Partial Depth Spall
Repair, and the SIKA Concrete Restoration at
http://www.sikacanada.com/eng/constr/cat/cr/index.htm.

Regards,
Harold Sprague


> -----Original Message-----
> From:	MSSROLLO(--nospam--at)aol.com [SMTP:MSSROLLO(--nospam--at)aol.com]
> Sent:	Wednesday, March 29, 2000 1:32 PM
> To:	seaint(--nospam--at)seaint.org
> Subject:	Old Concrete Repair Question
> 
> I have a project with an older building (built in 50s I think) that has
> some 
> of the concrete spalling off .  The building is a concrete beam/column
> system 
> with about 6" concrete walls and concrete roof.  To date, all I see is the
> 
> clear cover spalling off the main beams and some roof purlins/joists.  I
> do 
> not see any major damage to the section other than this spalling.  It is 
> spalling back to the tension reinforcing/stirrups.  
> 
> Any good suggestions for providing protection of the steel?.  The inside
> of 
> the building has fairly high humidity.  Water is used in their process.  
> 
> Also, does anyone have an idea what was "considered" minimum reinforcing
> back 
> in the 50s.  We do not know what reinforcing was used during the original 
> construction. I was wanting to estimate the beam strength based on current
> 
> code requirements.
> 
> Thanks
> Ron Martin
> Tuscaloosa, AL
>