Since you're in Georgia, it's not likely the cause is due to freezing/thawing and road salt like we have here in Ohio. To benefit from any repairs, I'm thinking you'll have to get to the base and make sure it's solid. Making repairs over a poor unstable base will waste the dollars you can spend on removal and repouring new concrete.

What is the age of your home/driveway and garage floor?

Michael

Hard to know how old the garage and driveway are. They were almost the last parts of the house to be built, I think. THe original house was started in 1938 in a vacation community. Like all the other original houses, it was only meant for leisure. And like most of the others, it grew bit by bit as people started to live in the community year-round. It has 3 separate foundations, but that doesn't count the slab on which the garage sits.

I'm afraid you're correct, and that it will take horrifying time and expense to correct the garage floor problems. The driveway should be easier, but perhaps it will have to be broken up and hauled away in pieces, and that's an enormous amount of stuff that will sit in a landfill somewhere, not to mention the cost. Ugh.

the garage is likely due to poor/no prep before pouring the slab. once the ground settled, the slab lost support and split. you can try concrete patch to fill the gaps, then paint or mats to cover it. i would also recommend getting a mudjacking company to come by and give you an estimate on fixing the ground under the slab.

as to the drive, many companies no longer haul concrete to the landfill anymore. they actually grind it up and reuse it to make new concrete. i have seen 2 new Walgreens go up in the last year and in both cases they ground up the old parking lots and mixed that up to make new concrete for the new lot. check to see if anyone does this in your area. if not, the other option is to check and see if anyone wants the chunks for erosion control. many people here line the ditchbanks with old concrete chunks to keep them from washing out.

1938 in Georgia. The concrete may well be hand mixed ( nothing intrinsically wrong with that) using local sand dredged from a stream. Often such concrete was mixed "brown" with too much sand and too little cement- still in the Great Depression. It may be only about 2" thick. If the above is the case, removing it will be easy. Use the finer parts of it to fill low places in the garage floor dirt and tamp the dirt well in prep for the new concrete.

Thanks, everyone. Bus Driver, I will try to get a sense of how thick it is. Though the house was started in '38, I know the garage is a much later addition, but as with most houses in my community, people did whatever they could on the cheap. Depression or not, a lot of the owners in the 1960s - mid-1990s (when a lot of renovation began) put in some terrible stop-gap fixes that ended up staying forever (well, until me!).