How To Maintain a Driveway

All gravel driveways need maintenance from time to time. Armed with a tractor, grader blade and this guide you can whip those potholes and corrugations into shape in no time.

GRADING TECHNIQUES

A variety of techniques can be used depending on the conditions associated with your driveway.

Ripping - breaking it up

Ripping is a method of breaking up the driveway surface by dragging prongs into it. It is useful where the driveway has become "slick" due to most of the gravel being compacted below the surface by vehicular traffic. Ripping drags this compacted gravel back to the surface.

When ripping, it is important not to dig too deep to avoid disturbing the larger gravel at the base of the driveway. As a guide do not rip any deeper than 50mm. Driveways are generally constructed with a larger grade of gravel (approximately 50mm) at the base. Larger gravel is used as it is less likely to sink into the ground underneath and it provides bigger gaps for water to drain away.

Smaller gravel (12mm down to 6mm) is used at the top because it tends to bind in on itself and therefore stays in place. Smaller gravel also provides a smoother surface.

So if you dig up too much of the larger gravel from the bottom of the driveway it will compromise the structural base. The larger gravel will also tend to tumble out to the side as car tyres run over it.

It is inevitable that you will scratch up a few larger pieces of gravel. There is no need to be overly concerned, simply use the tractor hydraulics to raise the grader slightly so the ripper tines don’t dig in quite so far.

Ripping is also useful if the driveway is particularly hard or corrugated as the grader blade tends to just skip over the surface. Breaking up the surface will then enable the grader blade to do its' job.

Some grader blades come fitted with rippers, some don't. Keep this in mind when shopping for one.

Grading - it's all about the angles

Grading is using the cutting edge of the blade to cut into the surface and move larger amounts of gravel to the desired location. This enables gravel to be pushed from the edge of the driveway back into the car tyre tracks. It also enables desired angles to be cut into the surface for water drainage.

If the driveway is in on a flat piece of ground the aim is to have a "crown" - refer diagram 1. This means water flows off either side of the driveway and down drains on either side.

If the driveway is cut into the side of a hill, the driveway should then be sloped in the same direction - refer diagram 2, so the water continues to run down the hill.

Angles on the grader blade can be easily adjusted in a number of ways to achieve a variety of results.

Tilting the blade back causes the cutting edge to dig in less giving a less aggressive cut. Conversely, tipping the blade forward causes the blade to cut in more for a deeper cut.

This adjustment is easily achieved by shortening or lengthening the top link on the tractor. By adjusting the side links on the tractor it is also possible to put a tilt on the grader blade. This is ideal for cutting a slope into the driveway for water drainage.

The grader blade can be pivoted on an angle so that the gravel all tends to run to one side – again this can be used to drag the gravel back to the middle of the driveway.

Backblading - finishing touches

Backblading as the name suggests involves turning the blade backwards so the cutting edge is not exposed. This is more of a finishing off process as it just pushes loose surface material into position rather than cutting in.

OTHER TIPS

A few simple adjustments of the grader blade will enable the blade to be put out to one side of the tractor rather than directly behind.

This offsetting makes it easier when grading up close to objects such as retaining walls as you don't have to worry about the tractor hitting the object.

Offsetting the grader blade can also literally prevent grading from being a "pain in the neck" as you don’t need to turn your neck quite so far to see what is happening behind you.

Putting more gravel down

If ripping and grading simply isn't enough to restore your driveway it may be necessary to top dress the driveway with more gravel. It is ordered in cubic metres. To calculate how much you need simply multiply the length by width of your driveway by the desired depth of material. (Note it is important that all dimension used are in metres.)

Example: (in metres)

Length (25m) x width (3m) x desired depth (.05m)
= cubic metres required (3.75m3)

There are a variety of gravel types and sizes available. Talk to your local garden supplies or even deal directly with a quarry for larger quantities.

Quick Touch Up

If your tractor has a 4 in 1 bucket it is possible to do a quick touch up to keep your driveway in good condition. You don’t have the same degree of adjustment of angles that you do with a grader blade but it is easy to give it a tweak as you are simply passing by.

Open the bucket to expose the cutting edge and tilt the bucket forward, drive forward and gently scrape the gravel to break up the surface. Close the bucket, reverse back to leave a smoothed out surface.

There are a variety of gravel types and sizes available. Talk to your local garden supplies or even deal directly with a quarry for larger quantities.