Hank
Member
Does anyone know where a good discussion about gravel under concrete might be found other than elastic discussions on pavement composite sections.
This was under the IBC about ten years ago. I certainly wouldn't discount the settlement issue that you raised but I made everybody aware of the situation and nobody threw a flag.Mark K said:ICEYou may have solved the problem of reinforcing cover but I would suspect that over time as the 3' of gravel consolidated over time that the footing would continue to settle. One of the limitation of the IRC is that it doesn't deal well with these sort of situations.
Slurry lots of slurrykhsmith55 said:Agree with knightj, we have the same problem with expansive soils here. The Geotechnical Engineers express the same concerns and also recommend eliminating the gravel under slabs on grade and pour the slabs directly on compacted earth.
A respected engineer in these parts that concentrates on swimming pools, recommends 6" of 3/4" rock under flat work around a pool. His take on it is that as the soil expands, it will push into voids between the rocks rather than lift the deck. Along with that, he requires a 6" wide, 12" deep perimeter footing and any trenches beneath are to be compacted.khsmith55 said:Agree with knightj, we have the same problem with expansive soils here. The Geotechnical Engineers express the same concerns and also recommend eliminating the gravel under slabs on grade and pour the slabs directly on compacted earth.