Need Help Framing a Turn-Down-Slab

[Omega Woods]

Not an expert at this by any means but this guy is.

 

[Chewwy]

As previously described, the guy who built our forms use 2x2s for the forms for a 5 1/2 inch thick pad and they were placed about every 4 ft. Our soil is mostly red clay that is slippery that owl s _ _ t when wet and hard as bricks when dry.

If you are unsure you could use 2x2s every two feet.

But considering everything, the metal stakes might be the best option and are unlikely to cost that much relative to the cost of the concrete, forms, rebar, wire mesh, and labor.

They will certainly be much easier to drive in the ground

 

[MossRoad]

Not an expert at this by any means but this guy is.

He said something about lifting the wire, but I never saw them lifting the wire, and they were finishing it and the wire still appeared to be flat on the plastic. I think it's about useless if it's at the bottom of the slab VS embedded in the center of the slab.

I'd have preferred to see them put it up on chairs so it stayed suspended in the concrete.

If I missed something, ignore the comments. I just didn't see it.

 

[MossRoad]

...

2) How do I get 4 runs of re-bar to hold together. I know there are rebar chairs that will hold the bottom 2 off the bottom but I don't know how to elevate the top 2.

You could make some u-shaped pieces of rebar to look like giant staples, then push them into the dirt to the depth you want the upper run of rebar to be. Then tie the horizontal runs of rebar to each side of them at the desired heights.

Rebar is cheap and you can bend u-shapes with your knee and hands pretty quick. Or use a rebar bender, as they are cheap as well.

 

[LittleBittyBigJohn]

Ordered the materials. Not as bad as I was expecting. $1,360

15 pcs - 2x4x20
40 pcs - 1/2x20 rebar
120 pcs - 3" dual rebar chairs
1,000 pcs - Rebar ties
2 pcs - rebar wire twister
1 roll - 6 mil 20x100 plastic
12 pcs - 6x6 welded wire 8'x20'

 

[paulsharvey]

Might want to grab a bag or 3 of wire chairs.

 

[Mike1955]

That is some serious overkill - I'm certain the engineering simply calls for 4 bars - no hoops

He may have a dozer in there. Not an overkill then

 

[scootr]

He may have a dozer in there. Not an overkill then

My remark was based upon 30 yrs of Residential, Commercial, and Govt specified concrete work.
But you are right, he might put an M1A1 tank in there ... maybe it should be more excessive?

 

[paulsharvey]

The stirrups or hoops were suggested more as an easy/cheap way to keep the 4-#4s in place. Not being an engineer, I can't say how much difference there is between 2-#5s vs 4-#4s in tension/shear, but around here, that slab would typically just have 2-#5s. The hoops/stirrups where not suggested to add strength, just for ease of installation.

Edit: 0.20 square inches per #4 vs 0.31 square inches per #5; so yes, 4-#4s are 0.80 square inches vs 0.62 sq inches; so the quad 4s are significantly stronger then dual 5s.

 

[LittleBittyBigJohn]

He may have a dozer in there. Not an overkill then

Dozer is borrowed it won't go in there. But I do like the tank idea....