Old Concrete Beam Schedule - Interpretation
Old Concrete Beam Schedule - Interpretation
(OP)
Please see the attached concrete beam schedule.
How is the reinforcement placed in the T9 Beam?
Should these bars be bent or is my section correct.
I forgot to show the stirrups but I understand the placement of those.
Thanks!
How is the reinforcement placed in the T9 Beam?
Should these bars be bent or is my section correct.
I forgot to show the stirrups but I understand the placement of those.
Thanks!
EIT






RE: Old Concrete Beam Schedule - Interpretation
EIT
RE: Old Concrete Beam Schedule - Interpretation
There are probably a couple of top bars used to tie the stirrups, but they would likely be nominal, perhaps 2-1/2" square bars.
You probably should X-ray the beam to be sure.
BA
RE: Old Concrete Beam Schedule - Interpretation
My oldest cocnrete standard is the 1940 Portland Cement Association's Standard Specification for Concrete and Reinforced Concrete and it lists the allowable strengths for reinforcing as 18,000 psi for structural grade steel bars and 20,000 psi for intermediate grade steel bars.
Since your building is older than that, you should be conservative on what strength is assumed.
gjc
RE: Old Concrete Beam Schedule - Interpretation
I didn't think my interpretation was correct either, I was assuming they must be bent but was not sure. I will look for the profile T9.
Also I will see what those steel grades yield for a result.
Thanks.
EIT
RE: Old Concrete Beam Schedule - Interpretation
My interpretation is:
2-1" sq bars bottom
2-1.125" sq bars bottom midspan
2-1.125" sq bars top over supports
RE: Old Concrete Beam Schedule - Interpretation
RE: Old Concrete Beam Schedule - Interpretation
BA
RE: Old Concrete Beam Schedule - Interpretation
I'll check both 1.) 2 top continuous and 2.) Simple span 4 bars in bottom and see what kind of allowable live load I end up with.
I'm just trying to get a approximate allowable live load.
EIT
RE: Old Concrete Beam Schedule - Interpretation
Somewhere on the drawings it probably addresses the bar strength - higher strength bars might be referred to as "hard" grade.
RE: Old Concrete Beam Schedule - Interpretation
I analyzed a structure similar to this about 4 years ago. Here are some of the challenges I faced:
-My section was under-reinforced in shear. At first glance you seem to have lucked out and there is plenty of shear reinforcing.
-Development length can be an issue as you have to check bond.
RE: Old Concrete Beam Schedule - Interpretation
BA
RE: Old Concrete Beam Schedule - Interpretation
After running the numbers and seeing what kind of allowable live loads I ended up with it seems that there should be (4) bars at the top of the section over supports as you pointed out. Thanks for the info because at first with only 2 bars at the top things were not working out so well.
EIT