Rebar yield 3

[I-beam]

I'm analyzing a reinforced concrete building located in the northeast, built in 1974.
I have the original design drawings, which are very complete relative to rebar size, spacing
and dimensions, but no information on f'c or fy. I am comfortable assuming f'c = 2500psi,
but not so on the yield of the primary rebar, as 40ksi or 60 ksi.
Anyone know what the typically spec. rebar yield was in 1973 ?

 

[hokie66]

60 for primary bars, 40 for fitments.

 

[I-beam]

Hokie
60 ksi used in the early 70s ?

 

[Ingenuity]

Yes. See timeline of 1959. Link

 

[skeletron]

Here are some previous threads:

thread507-212150

thread256-252569

 

[hokie66]

My response was based on practicing in Virginia from 1970 to 1982. During that entire time, we always used Grade 60 for main bars. But admittedly, Grade 40 was still available. We always showed the grade on the drawings, but some folks relied on the specifications, which is unfortunate because the specs rarely survive.

 

[Guest090822]

1970 era was well into 60 ksi

 

[JAE]

In the late 1970's and into the 1980's the general fy for bars was 60 ksi except for #3 stirrups.
The bend radius, on fy-60 #3 bars resulted in cracking with the steel recipe used in those days so it was not uncommon to see fy=40 ksi used for stirrups.

 

[I-beam]

Thank you all !