In NC we use type ABC crushed stone as a base layer under either asphalt or concrete pavements. GA is probably the same. ABC stands for aggregate base course. It is manufactured crushed stone without screening, largest size about an inch, thus includes all the smaller sizes including dust. It is normally the least expensive manufactured stone product. Spread out and roller-compacted, it filters out soil below, and spreads out the loads above. Minimum thickness is 4".
ABC "sets up" so is difficult to fine grade, so many contractors will use a 2 to 4-inch later of #78 stone over it and fine grade. This will make the concrete thickness above a more consistent thickness.
4" is the minimum concrete thickness. For a driveway that may see larger delivery vehicles, you may consider 5", depending on the strength of your base soil and subbase structure. Fiber increases the toughness of concrete, making it less likely to crack under an impact load. A light welded wire fabric does a better job at this, but is more difficult to install correctly. Fiber is nearly foolproof.
Control joints should be cut in at regular 12 to 16-foot intervals. Make squares, or rectangles no more than 1.5 to 1 ratio. These can be scored during the initial surface treatment or saw-cut a day later.
On long projects use expansion joints between every third- or fourth joint. Plan this with your contractor for his preferred material. Typical products are asphalt impregnated board or closed cell foam board. Some use treated wood.
Work with the finishing crew on a watering schedule to keep the mix cool during the curing process. Typically this is done with a lawn sprinkler starting a day after finishing.
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