During a recent demolition I came across what appears to be a wire mesh supporting un-reinforced concrete. We used GPR scanning and could not find any reinforcing steel in the deck. Core drilling indicated that the slab was about 3 1/2" thick. The bar joists are placed about 2 feet apart. It looks like this mesh was used to support the wet concrete until it cured. We have not yet found any attachment of this mesh to the joists, but I assume that they are welded at some point (no screw tips seen through the flanges). Has anyone seen this before? Do you have any idea what exactly it is and, more importantly, what kind of load carrying capacity it provided to the concrete slab? New owner wants to verify that the slab can support 100 psf live load. We can do the calculations for the joists, I'm just interested in this slab. Thanks so much!