Concrete – Will a 4″ non-reinforced concrete slab support the swimming pool

concrete

I am purchasing a 7' x 10' portable above-ground exercise pool which holds 2200 gallons of water. I plan to set it on my concrete patio which is quite wide and is 4" thick, with no rebar in it. Will the 4" concrete slab support 2200 gallons of water? My pool will be delivered soon so I need to know as soon as possible.

Best Answer

Concrete is usually rated at 3,000 or more PSI, which is a measure of crush resistance. You won't come anywhere near that. So the question becomes one of crack resistance, and that's going to depend almost entirely on the integrity of the substrate.

If it was poured directly on organic soil, it'll probably crack. If it's on a good base of gravel, sand, or recycled concrete, it'll probably hold well. Really, though, a crack won't change the slab's ability to support the pool. I'd assume that the pool will be placed on a mat of some sort that would protect it against any edges or irregularities in the concrete.


Some calculations (which are approximate, but close enough to allow us to dismiss outright crush strength as a concern):

7ft * 10ft = 70 sq ft
70 sq ft * 144 sq in = 10,080 sq in
17,458 lbs / 10,080 sq in = 1.7319 PSI

As you can see, crush resistance isn't a concern. It's all about whether the slab has to span any weak areas in the substrate, which could result in cracks and surface offset.