rebar strength in 1958

huangyhg

rebar strength in 1958???
hi all,
i am looking at an existing building which references aci 318-51 concrete code.  the drawings (produced in 1958) call for 20 ksi rebar per astm a305.  i can't get a copy of this standard, as it is withdrawn.  does any know whether the 20 ksi steel is ultimate, yeild, or allowable stress. i know very little about the old aci code, and only know of 40 and 60 ksi rebar, so any help is appreciated.
thanks
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for evaluating the condition of bridges, the fhwa allows the following as a general rule.
allowable unit stress range from 18 to 25 ksi and are assumed to be fy = 40 ksi.  the range is for inventory, posting or operating.  i didn't think listing them was appropriate for your case so i just gave the range.
also, it might be advantageous to have a mill test of the material if it is critical.
regards,
qshake
eng-tips forums:real solutions for real problems really quick.
aci 318-63 lists it as allowable stress for working stress design (i saved my old books) never know when they will come in handy.
best tincan
tincan:  great thanks.  i suspected it was allowable stress, but couldnt be sure.  i know what you mean about keeping old books.  i am always on the lookout for old codes to add to my collection.  seems like all you old timers (no offense) are hording your aci books though....
thanks again