Rebar note on Plans from 1965 1

[stevenspm]

I am working on a building built back in 1965 and came across the following note about the rebar:
"All reinforcing bars shall be deformed bars (conforming to A.S.T.M. A-303) with a minimum allowable tensile strength Fs = 24000psi (A-432)"
Now I understand the A-432 and Allowable Tensile Strength tell me it is Grade 60 rebar, what I do not quite understand is the "conforming to ASTM A-303" because from what I have Googled, A303 is an old carbon steel spec. Has anyone else come across this doubling up of specs for rebar?
Thanks,
Phil

 

[spats]

Check out the attached document. I don't see any ASTM A 303 spec for rebar.

 

[stevenspm]

spats,
That is why I am slightly confused, I just checked using the A-432 as indicated on the plans and in the document you posted, thanks by the way? I do not understand why someone back then would have given a spec for Hot-Rolled Carbon Steel Strip of Structural Quality (A-303) and then give the min tensile strength and then give a spec for Deformed Billet Steel Bars for Concrete Reinforcement with 60,000 psi Minimum Yield Point (A-432).
Thanks again,
Phil

 

[hokie66]

Sloppy specification writing, I think.

 

[JStephen]

From googling around (and reading back up through there, I see you already posted this document):
Title: Steel Reinforcing Bar Specifications in Old Structures
Author(s): Gustav G. Erlemann
Publication: Concrete International
Volume: 21
Issue: 4
Appears on pages(s): 49-50
Keywords: deformation; reinforcing materials; reinforcing steels; strength; specifications
Date: 4/1/1999
Abstract:
Rehabilitating sixty-year-plus aged reinforced concrete structures requires knowledge of the strength of the materials furnished during that era. Reinforcing bars manufactured during that period generally were Grade 33 (228 MPa) with various patented deformation patterns (ASTM A 15-11). During 1928 the U.S. Department of Commerce recommended standard bar sized, semi-standard deformations, and Grade 40 (276 MPa) minimum. In 1950, A 15 specified all reinforcing bars as round (#3 through #11) with A 305 deformation patterns. In 1964, A 408 added sizes #14S and #18S, and two strength levels: A 432 (Grade 60 - 414 MPa) and A 431 (Grade 75 - 517 MPa). Finally, during 1968, ASTM combined all previous reinforcing bar specifications into A 615.

So...could that be a typo, and they meant A305? One spec for the reinforcing pattern, one for the material.

 

[hokie66]

I think JStephen has it. A305, not A303.

 

[stevenspm]

Thanks, for the information. I have attached a image of the note in question.
Phil

 

[hokie66]

That reads 305 to me, not 303. Note the difference between the look of the 3 and the 5.

 

[jayrod12]

That's 305 to my eyes as well

 

[hokie66]

Reminds me of an advertisement for an optometrist here in Australia, "Should have gone to Specsavers".

 

[stevenspm]

OK, I guess I need to get some new glasses.
Thanks for the help,
Phil