One-Way Slab?

[RaptorEIT]

Analyzing this existing rectangular slab for some additional loading. The slab was designed in the mid '50s and I don't quiet understand the details. It appears to be a one-way slab, with two reinforced monolithic beams spanning top to bottom within the 20' x 20' grid. With one side being 20' and the other side being 7', I would say this falls under the category of a one-way slab (L2/L1>2). It looks like they did design it as a one way slab with temperature and shrinkage steel placed at 12" centers going left to right, and the main reinforcement at 10" centers going top to bottom.

Am I looking at this right? To me it looks like the temperature and shrinkage steel should be going top to bottom and the reinforcement steel left to right, since the one-way slab action is left to right.

Thoughts?

Thank you.

 

[JAE]

The primary steel, as you suggest, is running left-right on the page (see image attached).
The drawing note for the rebar is pointing to the "extent" of the bars, not the bar direction.
The red lines are the primary reinforcement that the note is referring to.
Hope this helps.

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[RaptorEIT]

Appreciate your keen eye, JAE. I see that now.

 

[SlideRuleEra]

Analyzing this existing rectangular slab for some additional loading.
The slab was designed in the mid '50s...

1950's means working stress design was almost certainly used, not ultimate strength. WSD may not address shear reinforcement adequately. Check shear.

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[RaptorEIT]

Thanks SRE, I'll look into it.