gravel and slab on soft soil?

[Neil2]

Re: gravel and slab on soft soil?

"However, after digging one foot I can push a piece of re-bar down about 3 feet in some places. "

I don't know exactly how hard you can push, but this sounds to me like very weak soil conditions.

Placing a slab on grade would likely give you some serious settlement problems. I would be tempted to continue to dig a test hole (rent a hand held posthole digger) down to firm ground. If this firm ground is in the order of 4 feet or so (or is uneven, i.e 3 feet at one corner, 5 feet at another), I would opt for a pile/pier type construction with a suspended slab.

If you can get some local expertize this would be good. It is worth fussing around at this stage.

[texman]

Re: gravel and slab on soft soil?

Is it in a low spot that has been wet or holds water? Is that typical soil stability in your area or is this spot different than surrounding soil?
Tex

[bluecrow]

I am re-siting my oven (due to dubious planning on my part) a few feet from an existing slab to a soil area that was filled and tamped 10 years ago. However, after digging one foot I can push a piece of re-bar down about 3 feet in some places.

Is this one of those "piers with feet -then a reinforced slab" situations, or is a floating slab on a couple of feet of gravel or concrete blend a possibility?

The oven will be a 36" Pompeii.

Don