Driveway question?

[Harleymsn]

Last year we cleared part our land for the build site. I had cut most of the trees the year before, so I had a fellow with a D6 clear the stumps and do some leveling. I had a pole barn scheduled for Sept. 1 and with the Florida hurricanes, my part of Tennessee got the follow up rains. With all this combined, I had a real muck situation and trucks ready to arrive. Instead of the small rock and gravel that I had planned, we hauled in 115 tons of 1"x3" rock to provide a solid base. I am headed back in a few weeks and need to finish the drive. It is solid, but I don't want to try driving my Harley or the wife's car too much like it is. I was thinking of topping this with a load of 3/4" stone. Good idea? Or should I use something a bit finer?

 

[Outlander1]

Here is how I like to build them but this just me.....Have the dozer dig a trench which removes all top soil the width of the drive. I think a foot deep is a minimum actually. Fill the trench with 8 inches of #3 crushed rock (big guy's) and run the dozer over it to compact it completely. Fill the remainder of the trench with 2RC which in PA is a State approved road bed material. Again compact it with the dozer. Then top with #2 crushed limestone. Make it a tad thicker in the center so it hopefully drains to the edges. The limestone should get you somewhat above ground level. In my area this will last quite a few years before it starts to sink. If you want to get fancy, install french drains the length of the drive on both sides.

 

[drm]

Harley,

If you just want to get a good top surface and the base is stable you can add to what you have. I would use a t least 3" of crushed limestone gravel 1 1/2" max, well graded, with fines (limestone dust). In PA (again) it is specified as 2a crushed limestone. It is essential that you use crushed limestone and not river rock or bank run as it may be called (The round stones will roll under your tires). The gradation of the stone will allow the different size stones to interlock giving you a more stable base. It should be tail spread by the delivery truck then compacted with a vibratory roller.

If you want to start over the previous post is a good starting point. Add more compaction, geotextile, drains, etc.

Just my opinion.

 

[Harleymsn]

Ok, maybe I didn't make it clear in my original post. I have no thoughts of redoing what I have now, just want to top it. The base I have in now is about 6-8" deep of 1"x3" rock. It was dump spread with one load down the center and 2 more side by side, thus forming a crown for drainage. It was then compacted by the D-6, the dump trucks and the trucks involved in the barn contruction. I was really planning to use 3/4" rock on top, but wondered if I really needed some fine mixed in. I can see pros and cons to the fines. They could pack it a bit tighter, but I worry that it may wash out in heavy rains. I know not to use the round (pond) stone or pea gravel.

 

[bills47172]

you need the fines to help lock the stone together.

 

[EddieWalker]

Yup, you need the 3/4 to fine rock to finish it off and help seal it. The fines will compact and lock together the larger onces and give you the solid finish you need. Then you can either seal it later if you want, or just maintain it. Some material will always run off from rains and usage. You just have to stay on top of it.

 

[ccdck20hst]

One draw back of going with a mixture of fines and 3/4" or less stone is that you can end up tracking the fine particles everywhere you walk - including into your garage or house unless you carefully clean your shoes. I have a small amount of stone (about 30 tons now in total over 3 years) on my short driveway and the next time I get stone I will go with 1 1/4", uniform in size becasue I always track those fine particules on my feet into the garage and house (even if only at the door). Also, the tires of my car and tractor pick up those fine particles and leave 'em on the garage floor. Still, fine particles are better than mud! Charlie

 

[Harleymsn]

Thanks Eddie and CCD, that was my thoughts on the fine locking in the larger stone, but also the problem of washing away and the tracking issue. How about if I have them spread a load of fines and the the 3/4 on top of the fines? Does that sound logical?

 

[drm]

Based on the dozer compaction and usage you most likely have a very stable base and only need to top it to make the surface smoother. I highly recommend using a well graded stone mix with the fines. I also ride a bike and loose gravel is very tricky, especially when wet. The thickness should be 2” minimum and at least 2 time the max rock size. It will work it’s way though the base and will need to be topped over time.

The reason for the gradation is to have differing sizes of gravel to lock together. The fines are required for this and limestone will harden up when it is wetted. Although, if there is too many fines or if they are not limestone they will create a mucky paste on the surface. The fines/paste can be turned back into the drive and mixed with the larger stone if this happens.

I have a 950’ gravel drive (placed 120 tons of topping last Sept) and I have to turn over some areas but most is setting up good.

As far as washout, I belive that if the gravel is compacted well and well graded you should not have much problem. That is unless you have drainage crossing over the drive. Then you need a culvert. I had to install one after the first two rains after I purchased the property washed it out. Not problems since.

 

[EddieWalker]

I haven't experience a tracking issue with my gravel driveway. I prefer to walk on it to avoid tracking dirt and mud.

If you have a tracking issue, you might consider topping it off with a small river rock type finish, oil sand or pavement. But that's another topic.

The crush, or road base material only comes with fines mixed in. From what I understand, it's what comes out from the crusher with the largest size designated to survive the process and the smaller stuff is also included down to fine dust.

Once compacted, it becomes one solid material due to the fine particles filling in the spaces between the larger ones.

I try not to overthink these things, and rely on proven methods that others have figured out over time.