I asked this question many years ago. Here is the answer I received from a helpful person:
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The "standard" around here seems to be what is locally called
"inch and a half crusher-run" limestone. This aggregate
varies in size from 1.5" down to almost powder. At the quarry
it was not screened. The fines in this mix pack very tightly
and supposedly form a seal that helps prevent water from
percolating into the clay (or whatever) below, and also help
keep the clay from rising up into the stone. The surface
hardens to a concrete-like feel, but it *will* erode if water
runs down the surface on a long slope. Having a crown on
the road surface will help, but it may be difficult to maintain
a crown over the years.
Limestone weighs roughly 1.4 tons per cubic yard. A large dump
truck can haul about 20 tons, but I've had 30 tons delivered in
a single truck (probably overweight by law). You can order the
stone by the ton rather than by the truckload. The supplier can
determine the best way to load the trucks. And don't hesitate
to call more than one place and ask for a quote. They'll want
to know to where they are delivering before giving you a price,
of course.
You will probably want the truck to "tailgate" (spread) the stone
on your driveway. To do this, there must be a lot of overhead
clearance. When the truck bed is raised, it is quite high.
You said your driveway was flat, but if some other reader has a
steeply sloped driveway, they should know that the driver will
probably want to tailgate downhill to avoid the risk of standing
the dump truck up on end.
If possible, have the first loads of stone spread at the road end
of your driveway. That way the other trucks can drive over the
first load(s) and help pack it as they deliver subsequent loads.
Amount Needed for each 100 feet (in tons):
----------------- Thickness ----------------
| 4" 6" 8" 10" 12" 14"
|
Width 8' | 15 22 29 36 43 50
Width 10' | 18 27 36 45 53 62
Width 12' | 22 32 43 53 64 75
Width 14' | 25 37 50 62 75 87
For example...400 feet long, 12 feet wide, 10" thick would
require about 53 x 4 = 212 tons or roughly 10 truckloads at
21 tons per truckload.