Hello. I can help. Can I get back to you tomorrow?
Hello. What is the span of the slab?
What is the location of the bars in the depth of the slab?
4' on center is much too far apart for code provisions. It will allow too much cracking and won't provide even minimum reinforcement
18" is the maximum allowable spacing.
You'll need #5 bars at 18" on center maximum. I'll get the allowable load on that now.
That will get you a live load capacity of 200 psf.
Hello. Do you have any other questions for me on this? If you could rate my answer, I would appreciate it.