Looking for a roller....

neilly2 · Aug 21, 2004

I couldn't respectfully disagree more. If I had to pick one application to compact with a tractor tire it would be the basement. A basement slab is set on several inches of stone which will bridge the occasional soft soft spot and the load is spread out. Additionally a house foundation will see minimal dynamic loading in relation to the bearing capacities of even poor soil.

The driveway will only see dynamic loading. Worse off it will be in the same location all of the time -- the path of the two tires. The poster stated an 11' drive which is one lane. The repetitive loading will create wheel ruts just like on the highways.

Why would you want to skimp on this for a couple hundred bucks?? The drive is a high profile area (it should look good) and what a nightmare fixing a settled asphalt drive.

Soundguy · Aug 23, 2004

( I wouldn't compact with tractor tires for state highway construction or a home foundation )

You would be surprised. I've built building pads for florida power substations that have been in place now for 12 years with no settling.. and compacted with a piece of equipment with some ballast.. no rollers on the job. Compacted in 4" lifts.. just had a pan and a d-4 dozer on the job.

PSI is all that counts when the density test passes.

Soundguy

neilly2 · Aug 23, 2004

What material are you compacting in Florida? My guess would be sand, which is fairly easy to compact since it doesn't hold excessive moisture and has consistent grain size.

We're all kind of debating something that can't be applied accross the board. As a civil you know that compaction depends on the type of material and the moisture content. If not in the optimum moisture range, no amount of rolling or vibrating will make it reach compaction. We don't know what the variables are where the poster is compacting.

Personally, if I'm in doubt I take the belt and suspender approach, rather than have to correct something later. I have a low tolerance for doing things twice.

Pressure alone won't necessarily acheive compaction to specified density.

jim_wilson · Aug 23, 2004

Not sure if this helps or not but the driveway area I will be compacting has been dug down to clay ( or what I believe to be clay ). I will then have to bring the area back up to grade with some sort of fill. Previous posters have recommended a rock dust 3/4 stone mix and or a 3/4 stone gravel mix. I am located in New England (Northeast MA) so some of the other materials that were recommended as fill ( limestone etc.) probably won't apply up here. I have been gotten compaction advice that ranges anywhere from " wet it down and drive over it with the tractor " to " you will need a large pavement roller to really get it well compacted". I am willing to listen to any advice so if somebody needs specifics to help please let me know.

neilly2 · Aug 23, 2004

If the clay is virgin soil that has just been exposed with your dozer blade or FEL. Its fairly straightforward, if its wet leave it alone (not vehicle traffic) and wait for a few hot sunny days. It'll bake as a hard as a rock. Then bring in the road mix (sometimes called DGA or 3/4 mix). I assume you will put down 4-6 inches.

With the stone mix your compaction activity just got easy, the only thing is vibration is mandatory with this. You can accomplish this with a walk behind plate tamper for $100 dollar day rental. If you don't want to walk it you can get small rollers (i'd lean towards this for a little more weight). It'll take a few passes and its ready to pave.

Soundguy · Aug 23, 2004

( What material are you compacting in Florida? My guess would be sand, which is fairly easy to compact since it doesn't hold excessive moisture and has consistent grain size.
)

Yep.. clean fill...

( We're all kind of debating something that can't be applied accross the board. As a civil you know that compaction depends on the type of material and the moisture content. If not in the optimum moisture range, no amount of rolling or vibrating will make it reach compaction. We don't know what the variables are where the poster is compacting.
)

Also true. When we roll limerock.. we generally have to wet it if it is too dry... hard to get lbr otherwise.. plus mosture is off.

( Pressure alone won't necessarily acheive compaction to specified density.
)

I wish most people here knew that as well. I have to chuckle to myself when I read posts about people rolling and 'compacting' graves and stone. ( not fines or dust ). In the past I've made a few posts that at best, they were consolodating voids int he gravel.. but were achiveing no real compaction. As an exercise i suggested getting a handfull of ball bearings and squeeze them in your hand till it turns red.. then open up your hand and see how compacted they are... It's about that time I get a sarcastic email or two and bow out, and let them compact their gravel driveway till their hearts content.

Soundguy

gabby · Aug 23, 2004

Around here I can get good sand/clay fill for $65 per tandem load. Crushed rock is $250 and up. Do the math and see how you can save a ton of money on your sub-base. The sand/clay compacts very well with tractor tires and it percolates too. The treads apply very high compaction forces where they contact the dirt so if you make enough passes with enough dead weight on the tractor and the proper moisture in the fill you will get very good compaction.

I would fill the bottom with sand/clay fill if it's available in your area, and top it off with crushed rock, using your tractor for spreading and compacting all of it. As you spread it, you're also compacting it with every pass of the tires. I've spread and compacted many loads this way for my barns and driveways.

Of course the ground doesn't freeze down here in paradise so that might make a difference! /forums/images/graemlins/smile.gif
Gabby

SteveBenson · Aug 24, 2004

Jim,

I live in Ct and put in a driveway a few years ago. They removed all the top soil, down to the sub soil, which was about a foot. I think he then put in 8" of bank run, and 4" of 3/4" processed. He compacted it with the tracks of his excavator. He told me to try not to drive in the same spot down the driveway for a few months, especially after a heavy rain. He said the processed gravel would pack down very well by itself in a few months. It's been 4 years and I've never had to even grade the driveway. All I had to do was add a couple buckets of processed to the end of the driveway where everyone turns out. But that was after 4 years and we regularly have tri-axles deliver material quite often (they are murder on a road when they turn). Normal maintainence for a gravel driveway I'd say.