Rather than lime, we use actual cement dust delivered and spread by a truck and then tilled into the native soils to about 12" depth. The process creates CTB or cement treated base and works very well here in the valley soils.
I've got some wet spoogey clay to build roads in. I have learned that naked clay, even shaped with a steep crown, will become spooge if you drive on it during the wet season or when it is not dry and cracked. The spooge leaves ruts, the ruts fill with water, and the clay becomes a deep spooge hole. Stay off the naked clay unless it is dry.
Once that same naked, clay, crowned road gets as little as 3 inches of 1.5 inch rock on it, the road is drivable and will remain drivable year round with moderate loads. The clean rock keeps the surface from pumping into spooge and the crown shape is maintained. Adding a top layer of crushed rock, I like 1.25" minus, is a long term solution for a permanent road since it will actually prevent the water from getting to the clay.
Clay is funny. Water won't move through it, it is nearly waterproof but when water is present the clay becomes spooge if you work it at all.
Once it is spooge, it takes a lot more rock to make it solid and then you will have a non-crowned clay subgrade so you'll want to top it with crushed right away.