Pouring large slab on red clay.
Pouring large slab on red clay.
(OP)
Hello! Me and my father are looking for some advice on pouring a 7200 sqft slab on top of red clay. We are looking to purchase an indoor tennis court that was built with clay. (Red clay.) We have gotten many mixed opinions on this matter and we are trying to figure out whether or not to pull the clay out first. The clay is only 4" thick, and we are looking to pour a 6" slab on top. Will a few inches of gravel and a ton of rebar be OK on top of the clay? The court was certainly compacted heavily over the years. I have heard from some masons that the clay can cause the slab to crack and sink down the road. This is going to be a very expensive pour and we want to do it right. Any input is appreciated. Thanks!





RE: Pouring large slab on red clay.
RE: Pouring large slab on red clay.
I agree it is a better idea to rip up the clay. Yes, we have professionals lined up to do this. I'm just trying to get another view on this matter being that I have gotten contradicting opinions. It looks like we are going to rip up the clay. I appreciate your input. Thank you.
RE: Pouring large slab on red clay.
RE: Pouring large slab on red clay.
RE: Pouring large slab on red clay.
RE: Pouring large slab on red clay.
http://www.jlconline.com/architectural-mesh/post-t...
RE: Pouring large slab on red clay.
RE: Pouring large slab on red clay.
RE: Pouring large slab on red clay.
As cvg noted, this is an interior clay court and thus not exposed to rainfall. Since the "clay" used for the court is generally not expansive anyway, I would put this at a low risk for movement of the slab. Having said that, the permeability of the "clay" is relatively low and is susceptible to capillarity, so if the water table is within a few feet of the bottom of the material, I would remove it since the concrete will be a capillary barrier and water imbibed by the material will get trapped there, thus lowering its stability as a compacted base material.
Have a simple Atterberg limits test run on the material by a local lab. The cost is nominal (usually less than $100 US) and you will find that the material is likely non-plastic or very low plasticity.
Considering the small amount of material, it is easier to take it out and feel comfortable about it than worry otherwise.