rebar and stirrups

[markrahn]

For all you guys who have experience with things of concrete. Specifically monolithic concrete slabs. I am building a 40 x 60 with a brick ledge all the way around. So the forms are building out to 40' 11" x 60' 11". The footings are dug so from the bottom of the footing to the top of the slab is 32 ".

I am doing my own steel work, so I want to know what size stirrups I need and how far apart to space them.

How far off the bottom of the footing does the bottom runs of rebar need to be?

How close to the top of the slab does the top runs of rebar need to be?

How many runs of rebar do I put in the footings?

Should I "tie" the corners with diagonal runs of rebar?

Can You tell I am a rookie?

By the way. Man has the cost of rebar gone up or what:confused2:

 

[arsenix2001]

I dd foundations and retaing wall footings for a living. Most were engineered. First off you are going to need a rebar bender/cutter and the fastest way to secure it is with quick ties and a twister. You should be able to get all of this at an industrail supply. What is needed may vary greatly depending on structure load and goegraphic area. I would strongly rec. Getting an engineer involved. I will make recommendations on the heavy side and assume your slab will be structual as you will pour mono. Max spacing on your footing bar should be 12" oc with cross braces at 16" oc. Rebar should be roughly 4-6 off the bottom, and i would use #5 grade 60 for the runs. You should bend L shaped pieces for the corners so the running bars are continuous. Use at least a 12" overlap on the running bars. Your slab can be a grid of #4 grade 40 rebar with 12"x12" spacing twards the top of the slab. If your pouring 6 inches, go for 4 max hieght. That grid needs to be well tied to the footing rebar using downturned L bends again with a 12" overlap and then tied to the running bars in the footing with lateral bars bracing the downturned Ls in the footing, so its all nice and locked together. Do this and that puppy wont be going anywhere. Use a min 3500psi 4-6% air entrainment. Hope this makes sence.

 

[markrahn]

The footing or stem wall? is about 12" wide. how many runs of rebar through the footing? 2 on bottom 2 on top of the stirrup? Man, that is a bunch of rebar huh?

 

[arsenix2001]

The footing or stem wall? is about 12" wide. how many runs of rebar through the footing? 2 on bottom 2 on top of the stirrup? Man, that is a bunch of rebar huh?

Yes that should work, and yes your talking quite a few tons of bar... May want get a helping hand or two just due to logistics, one extra man can speed the process 150%. A gas cut off saw helps loads too. There may be some that say you could use road mesh for the slab and tie the Ls into that. If it were my building I would want a structual grid. Feel free to pm any question if i lose the thread.:thumbsup: