Smooth farm tracks are kind on machinery, livestock and operators, allowing a little extra speed to deliver increased productivity with less downtime. Geoff Ashcroft visited a Somerset farm track renovation specialist to see what’s involved in restoring the finish.
Like our country’s roads, heavily used farm tracks have a tendency to deteriorate over time. Once pot-holes start to appear, regular traffic will repeatedly bash them harder and harder, and it is only a matter of time before the surface of a farm track resembles that of the moon.
Crashing your way along worn-out tracks is one of the quickest ways to incur machinery repair bills, not to mention the impacts on operator comfort and livestock health. Though putting them right extends way beyond simply filling in the holes.
Gareth Creed, director of Yeovil, Somerset-based track renovation and cement stabilisation specialist, Dave Creed and Sons says; “There is only so much discomfort that tractor cab suspension can absorb. The only course of action is to re-lay the surface, to create a smooth, tight finish.”
Farm track renovation has been part of the Creed family’s repertoire since 2002, when the business moved towards groundworks to supplement its agricultural contracting operations.
Each year, the firm builds about 15 miles of tracks and renovates a further 20-25 miles across southern England. Typical renovation costs are from £10 per linear metre, with cement stabilisation priced form £32/metre.
“Good drainage is also important for surface longevity,” says Mr Creed. “If the track has sunk and the edges are higher than the surface, there is nowhere for surface water to go. Puddles and flooding will soon see aggregates eroded away and potholes then quickly develop.”
He says that most track renovation projects can be carried out without removing or investing in new materials. “Most of the time, we can recycle what is already there.
“We can regenerate the track materials and leave the surface needing only light maintenance. And for those tougher applications, we can add cement stabilisation into the mix, to create a very tough layer that also suits heavier machinery. This is particularly useful when sub-layers are soft and prone to movement.”
He adds that where cement stabilisation is required, a 3m-wide track can consume approximately one tonne of cement every 10m, with the stabilisation process incorporated throughout a 200mm layer. “Cement stabilisation does add a lot of strength and rigidity below the surface,” he says.
The track renovation process starts by first addressing any outstanding drainage requirements – it could be re-cutting a ditch or clearing away the edges of a sunken track, so surface water is able to run-off. “Depending on the existing track’s construction, we can run a front-mounted ripper in combination with our tractor-powered stone crushers to assist with processing the surface,” says Mr Creed. “It is a bit like cultivating a seedbed – we need a loose, fine finish that can be worked and graded into a smooth track, before being tightly compacted.”
Mr Creed says it is important not to include soil. “If there is a build-up of soil on the surface, we will dig that off first,” he says. “And at that point, we may need to bring in some aggregates to raise the surface and achieve the desired finished height.”
The firm operates two tractor-mounted stone processors - a SuoKone Meri and a Kirpy. Both are 2.5m wide and are used with either of the firm’s New Holland T7 tractors. “We use AutoCommand transmissions for their infinitely variable speed control,” says Mr Creed. “And with 210 and 270 models, there is no shortage of power. Importantly, the tractors offer weight and stability to handle the heavy stone processors.
“The SuoKone Meri does not need a ripped track – it can go straight onto the surface to mill the top layer into fine pieces through a depth of 50-100mm,” he says. “The Kirpy is a much heavier duty machine designed to work to a greater depth – typically down to 200mm.”
With integral riddle behind the horizontal milling rotor, the Kirpy is able to separate aggregates during processing. Large materials will fall to the bottom of the worked area helping to create a sub-base, with smaller, finer materials passing through the riddle and landing on top.
“If we are processing a concrete track, we will use an excavator and hydraulic hammer to break the surface into manageable lumps that can be processed by the Kirpy machine,” he adds.
With the surface machined into a loose, fine aggregate, the Creed team sets to work on grading the surface with a 2.5m Rabaud semi-mounted, hydraulically operated grader. “It is very important to grade the surface several times to create a cross-fall or camber on the surface, to help with drainage,” he says. “This can take three or four passes to shape the top layer and create the desired surface profile. What we do not want is a flat, level track.”
Once grading is complete, the track is heavily compacted using a tractor-mounted triple compaction plate. This heavy-duty device uses three independently mounted vibrating plates that can follow the camber of the surface, unlike the fixed drum of a roller.
A couple of passes with the compaction plate will create a tight finish, resisting the ingress of water. “We will then run the grader back over the track surface just to lightly trim any remaining high-spots that might be left from compacting the surface,” says Mr Creed. “We will then re-compact the surface a final time.”
He says that when freshly laid, a farm track should be driven over with vehicle wheels positioned in different places with every pass. “We are all creatures of habit and will tend to always drive in the middle of a track,” he says. “It is good practice to straddle any wheel marks and run in different places on the surface. A renovated track will have strong edges too, so spread the load across the full width of the surface to use machinery as part of the maintenance process.”
Put down right, Mr Creed says a renovated track should provide at least 10 years good service. “However, a renovated farm track is not a fit and forget process,” he says. “If you want the best longevity, then periodic maintenance is required to prevent early track deterioration. Ideally, the surface should be re-graded every year to keep the top layer in good condition and to stop surface water collecting.”