New stone driveway - use geotextile fabric?

[BuilderML]

It all depends on the characteristics of the subsoil. Geotextiles do a couple of things: 1) spread the loads from the driveway over a wider area, and 2) maintain separation of the sub-base from the native soils.

If the native soils are weak, loose, wet, etc., fabric is certainly a good idea. If the native soils are well-drained sand and gravel, there's no need for a geotextile.

radair sums it up perfectly

 

[smbrooks]

Fabric is used when the soil isn't prepared properly or there isn't enough time to get the dirt work done. A properly built up road starts with creating drainage on either side of the road and a road base that is higher then the drainage and compacted. If neither of these basic first steps are done, then fabric is used to compensate. Like the others have said, it supports the rock better and allows you to get through those problem areas. The drawback is that you will spend more money on the fabric and you will need more rock then if it was done properly with dirt.

Eddie

I think if you research the topic that you'll find that using geo-textiles or grids often reduces the cost of the road because it allows you to minimize or perhaps even avoid subgrade over-excavation. Engineered fabrics and grids help to bridge poor, wet soils thereby resulting in less expensive construction and minimal environmental impact. I don't know what the soil is like in Tyler, Texas but I can tell you fabric is the way to go in Missouri.

If you poorly design, compact, or drain a road, fabric won't save you. It's better than not using it, but the road will still fail sooner than one properly built and require more frequent maintenance. Proper engineering is assumed. It sounds like your experience with fabrics is as a back up to bad design, mine is as an integral part of a good design and for that reason we use less rock - not more, and get the same or better performance. Our experiences with geo-textiles appear to be different so our evaluation of its use is different. I stand by what I said.

Steve

 

[EddieWalker]

My experience is that people use fabric instead of building up the crown of their base and developing proper drainage on their road. While it makes sense to take from what they do when building highways and county roads, it doesn't really apply to what a home owner needs to do for a driveway.

Most will not buy enough rock in the first place. They also tend to dig a trench where they want their driveway, which just creates a place for water to collect once they fill that trench with rock. There is a rush to get from opening the area for the road to getting the rock on it instead of bringing in more dirt to build up the road base and compacting it properly. Of all the threads I've seen on here about building a driveway, I can't think of one where there where pictures of ditches created on either side of it. If you don't have drainage, it wont matter what else you do, it will fail.

For some, it seems like fabric is the great cure all for roads. While it will help, and there is nothing wrong with it if you want to spend the money, it does have its limitations and there is only so much it can do when trying to compensate for poor dirt work. My advice will always be to get the dirt correct first. Do whatever it takes, spend as much time as needed!!!!! In the long haul, the difference between a road that lasts and one that needs constant repair goes back to the dirt work.

Eddie

 

[smbrooks]

My experience is that people use fabric instead of building up the crown of their base and developing proper drainage on their road. While it makes sense to take from what they do when building highways and county roads, it doesn't really apply to what a home owner needs to do for a driveway.

Most will not buy enough rock in the first place. They also tend to dig a trench where they want their driveway, which just creates a place for water to collect once they fill that trench with rock. There is a rush to get from opening the area for the road to getting the rock on it instead of bringing in more dirt to build up the road base and compacting it properly. Of all the threads I've seen on here about building a driveway, I can't think of one where there where pictures of ditches created on either side of it. If you don't have drainage, it wont matter what else you do, it will fail.

For some, it seems like fabric is the great cure all for roads. While it will help, and there is nothing wrong with it if you want to spend the money, it does have its limitations and there is only so much it can do when trying to compensate for poor dirt work. My advice will always be to get the dirt correct first. Do whatever it takes, spend as much time as needed!!!!! In the long haul, the difference between a road that lasts and one that needs constant repair goes back to the dirt work.

Eddie

We agree completely. From your posts I know that you know how to properly construct a road and that is essential. I just want to add that fabric on a properly constructed road will add many years to the life of the road in those areas where the soil is poor (old pastures usually qualify) and further cut maintenance costs. Only in Colorado have I built roads that needed little sub-grade compaction. But, we had to blast those roads out of rock! I agree with you, of course, that there is no substitute for good design and execution. But modern technology has provided a material that inexpensively (in the long run) improves road design and maintenance. That material is geo-textile fabric. But it is not meant as a replacement for intelligent design.

My original post was in response to another post about a concrete truck that broke through a road. The builder had to repair the fabric and cursed the fabric. My point was - if the road had been properly designed and constructed the fabric would never have been exposed. And that's really what you are saying too, isn't it? The road wasn't well constructed and the fabric was a side issue.

And yes, amateur built roads tend to fail early and require constant maintenance and cost more in the long run. As you say, most people don't buy enough rock for the sub-grade. But, they'll pay plenty over the years for replacement rock as the base sinks into the soil. My point is, use the geo-textiles. It's a whole lot cheaper than adding rock every year. And, it will add years to the life of the road whether it is perfectly engineered or not. The payback time depends on the quality of the soil on which you build and a whole lot of other variables. This is a tractor forum after all and we'll save the enumeration of variables for an engineering forum.

Roads are expensive and we'll pay the price for them one way or another. Let's build them right and leave them for our grandchildren to enjoy.

Steve

 

[Ken45101]

They also tend to dig a trench where they want their driveway, which just creates a place for water to collect once they fill that trench with rock.

Yes, I have wondered about that too. A nice pond. A clay bowl. My first driveway project 15 years ago, the previous owner had dig a trench in seasonally wet ground. I continued that for a while but eventually just dumped #2 on top of the ground (clay) and let traffic drive it in and lock it together. AFAIK, that held up just as well as the excavated trench, and was a lot less work and cost.

 

[Lowrider2120]

I just did a new drive around 12' x 450'. I stripped the silty soil that was almost all fines, used fabric, 4" of #2 minus and 2-4" of 3/4" minus. Had five 10 yard concrete trucks and and a 50' trailer with my trusses loaded and it is now well compacted with no sign of failure at this point...time will tell. It is above the surrounding soil by 2" or more and should drain well. In snow country the Spring break-up seems to do more damage to gravel roads than any other time. Time will tell!!

 

[PineBrookFarm]

It all depends on the characteristics of the subsoil. Geotextiles do a couple of things: 1) spread the loads from the driveway over a wider area, and 2) maintain separation of the sub-base from the native soils.

If the native soils are weak, loose, wet, etc., fabric is certainly a good idea. If the native soils are well-drained sand and gravel, there's no need for a geotextile.

What he said!