describing the rather substantial concrete slab put in place at the oregon national guard armory in milton freewater, oregon i have opined that it might be as much as 10 or 12" thick. this makes it very strong, all by itself.
i noted, however, that i had not been there where the slab was poured, and that i did not know whether or not the slab was reinforced w/ steel reinforcing bar, commonly known as rebar.
well, now i know that it was. an old high school classmate lives in the area, and he witnessed the rebar being put in place over the course of several days, and described it as very substantial, doubled layered, criss crossed, and probably about 3/4's of an inch thick.
here is the updte to the original post on the matter.--
update, concrete & rebar: 10.31.2013. the building movers are just about ready to place the old building over the new concrete slab & foundation. chatting w/ another bystander, a fellow with whom i attended high school many years ago, i learned something of some interest. the concrete slab, as might be expected, has a whole mess of reinforcing steel bar in it, a/k/a rebar, and it was not used sparingly. my "source," who lives in the neighborhood, said that the rebar is double layered, "criss-crossed" as he put it, and that it is about 3/4" of an inch thick steel bar.
the slab is very thick. and, it has a lot of reinforcing bar in it. this gives this particular slab an incredible strength in both compression, and in tension & sheer shear. (think of "tension" as "sheer" "shear" with a lever attached to it.) as my old high school classmate says, "it ain't goin' anywhere." he might have added, without overstatement, " ... anytime soon." end update.
john jay @ 10.31.2013
caption: the shed, moved off its foundation, waits for the construction crew to finish lunch before it gets pulled into place on it's new concrete slab and foundation. the foundation walls are about 12" thick, and the slab is by my estimation around 10 or 12" thick, replete with a double layer of 3/4" rebar. i do not know what is going into that building, but, it is going to be very substantial, and very heavy.
p.s. read the little link below, "waffes ... ." the slab in milton freewater has this curious appearance, and i suspect the technique described in the post was used. maybe. but, it is an interesting post.
update no. 2, 10.31.2013. the building sits at its new situs. in situ.
caption: there the old dear sits, in her new location, looking sort of dowdy in her old rusty galvanized panels, and not at all resplendent over the brand new foundation and pad built for her.
it just gets curiouser and curiouser. i talked w/ some fellows, and they told me that the pad was thick, 7 to 8 inches seemed to be the variable assertion (i think it is much thicker, for all that is worth, and have the pictures to argue the same).
they did say, however, that the slab in the "new building" has a whole lot of rebar in it, over 400 pieces, and they said it was 1/2" thick, and the criss-crossed bars were laid on 12" centers. that, my friends, is a lot of rebar, and it gives that floor incredible strength in sheer shear and in tension. end update.