Preparation of the site is as important as the thickness of the concrete. Many home center stores carry pubs at reasonable cost to answer all your questions. Consider fibre added to the concrete at the plant, as can be less expensive than rebar, and result in a thinner(cheaper) but stronger slab. Also consider your local public library, but be careful to choose the latest books, as technology of the fifties( an old book) simply is out dated, the same way a black-and-white TV would be. Keep in mind also that concrete work is very, very hard work, and will probably be the most strenuous work you'll ever do, unless you are planning on giving birth, which, from my experience, is the hardest work of all...
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