On Sat, 02 Sep 2006 17:59:20 GMT, "mook Johnson"
wrote:

I'm going to be pouring a 3 x 5 slab 8" thick. 2" below ground and 6" above.
It will need to support about 500lbs.

I'll be using quikrete for this. Do you think I'll need rebar for this
small slab?


I'd use welded wire grid, an inch and a half from the bottom and top.

Either that, or place about half the concrete, and then dump rocks
in to bulk it up, and then another layer of concrete.
(Always assuming I could resist the temptation to cast
a storage vault under the damn thing.)