Gravel driveway help.

   / Gravel driveway help. #1  

mjncad

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My neighbors and I just finished installing new driveways consisting of 3" uncompacted CDOT (Colorado DOT) #6 recycled concrete road base that I compacted with my tractor. This was followed by 3" uncompacted 1" x 3/4" recycled concrete rock. My neighbor compacted his with his pickup, and I rented a 5-ton vibratory smooth drum roller for aggregate/dirt compaction for mine.

All looked great for a while...a short while before the stuff started squirming and moving on us. Now it appears we've traded our old mud bog in winter driveways for another problem, namely bogging down in the rock.

The road base compacted wonderfully; but looked like crap. The rock top layer compacted nicely, looked like we wanted it to; but isn't staying compacted.

I have a few tons of left over road base I'm thinking of spreading out on my driveway in hopes of getting it into the spaces between the rock to help lock it together.

My neighbor's driveway is about 3,800 square feet, and mine is about 4,050 square feet.

Any thoughts on how to cure our problem?

Thanks!
 
   / Gravel driveway help. #2  
Need lots of fines to work into the recycled concrete rock. Sounds like you didn't get any.
Just the 1" x 3/4" ends up like marbles.
 
   / Gravel driveway help. #3  
Need lots of fines to work into the recycled concrete rock. Sounds like you didn't get any.
Just the 1" x 3/4" ends up like marbles.
What he said .... :thumbsup:
 
   / Gravel driveway help. #4  
For starters, the soil under the gravel driveway must be well-drained and strong. It also must be free of any organic material like sticks, tree roots and leaves or grass. All topsoil must be stripped off the driveway location and stockpiled for use at some other place on your lot. It is a very bad practice to build a driveway on top of spongy topsoil filled with organic debris.

Water is the enemy of gravel driveways and any roadway. Surface water can erode the gravel off the surface of the driveway and subsurface water can turn strong subsoil into a quagmire. The weight of cars and trucks pressing down on a gravel driveway is not much different than the powerful hydraulic pressure used on construction machinery, car lifts and any other machine that uses the leveraged force of hydraulics.

Water that is forced under pressure under the gravel can transport silt from the subsoil into the gravel. As the silt squeezes between individual pieces of gravel, it causes the friction bonds between individual pieces of gravel to weaken. When this happens, your gravel driveway can fall apart in no time.

It is often a great idea to install a geotextile fabric on top of the subsoil before the first layer of gravel is installed. This fabric prevents the silt in the subsoil from fouling the gravel. These products come in wide rolls and can easily be installed by two people who just unroll the fabric allowing it to lay on the soil. On windy days it needs to be covered quickly with a 4 or 6-inch-thick layer of crushed gravel. If you don't do this, the fabric might end up on your neighbor's lot.

The first layer of crushed gravel needs to be a larger-sized gravel. Try to locate stones that are the size of baseballs or even softballs. Never use gravel that is rounded as each piece can move easily when pressure is applied to it. Angular gravel interlocks with adjacent pieces and the combined mass can act as on larger piece of rock.

Add additional layers of crushed rock in 4-inch thick layers with each layer being a smaller sized stone. Compact each layer with a mechanical roller or tamping machine. The final layer of gravel should have pieces of angular stone no larger than a golf ball, with many of the stones being the size of marbles. If you can install 10 - 12 inches of gravel on top of the geotextile fabric, you should have a gravel driveway that will last decades.

Be sure the gravel driveway has a crown in it. This means the center of the driveway is always higher than the two edges. The crown allows water to flow off to the sides of the driveway preventing any ponding of water on the gravel surface.

Gravel driveways need some periodic care in the form of grading or dressing. Low spots need to be filled with gravel scraped from any high spots. If your driveway has curves, you will discover that car and truck traffic tends to push loose gravel to the outer edges of the curves. This gravel needs to be brought back to the center and inner part of the curves.

Gravel driveways built on hillsides need ditches on the high side of the driveway. These ditches capture surface water that runs down the hill and otherwise would run across the driveway. Larger angular rocks should be placed in the ditch to slow down the speed of the running water in the ditch. Monitor the ditch to ensure the running water is not cutting too deep a channel or eroding the ditch causing failure of the gravel driveway.

OPTION 2 - The build up should go as follows - the first layer will be #3 stone (fist size); the second will be #57(little less than ping pong ball); and the final will be #21-A, or called crusher run (thumb nail sized stone with stone dust mixed in with it).

With a layered set up like this, you will have a driveway that will last many, many years.

Build A Gravel Driveway
 
   / Gravel driveway help. #5  
Regardless of how well built it is all gravel driveways require regular maintenance. I live at the end of a 1 mile long private gravel road. My lower neighbor maintains the 1st half mile and I the second half. Sounds like you have some settling issues going on. It's a waste of time and money to tear it out and rebuild it IMO so you're best bet is to devise a maintenance schedule after adding some fine particulates to help keep the rock from shifting. The most important rule we have on our road is SLOW DOWN. We have 10 MPH signs posted. Loose gravel is very easy to loose control on and the faster you go the more it will tear up your road especially when it's wet. :)7
 
   / Gravel driveway help. #6  
Again: what they said :D

45843d1128867796-new-driveway-polebarn-750769-img_0996.jpg


The above image was my new driveway as it was being installed back in late summer of 2005 - topsoil dug out down to clay, geotextile fabric laid down, covered with a base course of #1's & #2's, then topped with crusher run, which had tons of fines in it.

It was mostly compacted by us driving over it with our vehicles (cars, trucks, tractor) .... although having those dumptrucks roll down it loaded a time or two no doubt helped.

Five years later and it is holding up extremely well - there are one or two small places (shallow potholes) that need some minor attention - and they likely wouldn't even be a problem ...... if I could train my wife to not drive right dead-center thru the middle of them when it's wet out and there is a little standing water in the potholes :confused2:

It looks pretty much like a "dirt" road - but it's really not (so if you are going for a different aesthetic it might not be for you) - it's a rock road. I was going for solid roadbase and really didn't care about the initial looks - with the idea that it would eventually be paved, probably with asphalt.

When it is dry, it's about like concrete ..... when it's wet, it's softer (surface mostly) - but provided you don't spin the tires and drive like a maniac it will support alot of weight ... even when wet. It's solid enough that it really hasn't even developed any tire track ruts.

I have had to do almost zero maintenance on it .... although at this point it could probably use a little crusher run in a few spots, and it might be time to do the bi-annual "hit-it-with-the-landscape-rake" thing ......
 
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   / Gravel driveway help. #7  
I used crushed shale for the base on my short driveway. It is about 6" thick and has stood up to loaded concrete trucks and all sorts of tractor traffic. I was planning to put some crushed white marble as topping later, but it is holding so well that I may just leave it as is. The only problem I see with that is that it tracks in the small pieces of crushed shale into the garage from the tires. It seems to be pretty much impermeable to water. I had it spread, compacted with a dozer and after a few rains it settled into a near concrete like structure. It had a lot of fines that washed down into the stone and locked it all together. I can dig it with my FEL or box blade, but tractor traffic does not leave a mark.
 
   / Gravel driveway help. #8  
mjncad said:
My neighbors and I just finished installing new driveways consisting of 3" uncompacted CDOT (Colorado DOT) #6 recycled concrete road base that I compacted with my tractor. This was followed by 3" uncompacted 1" x 3/4" recycled concrete rock. My neighbor compacted his with his pickup, and I rented a 5-ton vibratory smooth drum roller for aggregate/dirt compaction for mine.

All looked great for a while...a short while before the stuff started squirming and moving on us. Now it appears we've traded our old mud bog in winter driveways for another problem, namely bogging down in the rock.

The road base compacted wonderfully; but looked like crap. The rock top layer compacted nicely, looked like we wanted it to; but isn't staying compacted.

I have a few tons of left over road base I'm thinking of spreading out on my driveway in hopes of getting it into the spaces between the rock to help lock it together.

My neighbor's driveway is about 3,800 square feet, and mine is about 4,050 square feet.

Any thoughts on how to cure our problem?

Thanks!

Put some fines on top of the recycled concrete. Recycle concrete has no bonding agents. So put down some sreenings or fines
 
   / Gravel driveway help. #9  
Put some fines on top of the recycled concrete. Recycle concrete has no bonding agents. So put down some sreenings or fines

Yup..Some powder would probably help. I use 2A with powder and it packs like concrete. My neighbors covered the last 500ft of our road with straight 2A without and fines...That stuff is moving all over the place. Like driving on a pillow. My 500 FT with the powder is like cement.
 
   / Gravel driveway help. #10  
alot of quarry's find fines to be a problem some have million ton fines piles especially if they make alot of concrete aggregate, you may be able to find a good deal
 
 
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