Reducing ground pressure
With the work that we carry out on the moors and on
agricultural land it is important that the vehicles we use are designed to
minimise ground pressure to reduce compaction.
Compacted soils contain fewer larger pores, which have greater
volume for water filtration and drainage. This results in surface water standing on the surface rather than
penetrating and draining away. If on a
hillside or moor, this water becomes run-off, causing erosion. The potential for moorland to counter-act global
warming is great, with its ability to lock up thousands of tons of carbon in
its peat. It is vital to preserve and restore
our moorlands and prevent the the peat being washed away. On farmland, flooding not only causes crop
damage, but forces water straight into streams and rivers which can cause them
to flood their banks, as we have seen in recent weeks in Cumbria.
Ground pressure is measured in Pascal’s (Pa) which is then
corresponded to PSI. Average ground
pressure can be calculated by: average pressure = Net force/Area (p=F⁄A)
Increasing the size of the contact area of the machine to
the ground (footprint) reduces the ground pressure and therefore reduces
compaction and makes traveling on unstable ground less risky.
Below is some examples of ground pressures:
|Human male stood (1.8m tall, medium built)
|| 55kpa (8psi)
|Human male walking (1.8m tall, medium built)
|Horse weighing 550kg
|Horse weighing 550kg galloping
|| 3.5mpa (500psi)
|DTMS Alpine tractor and flail
|ATV (rubber tracked)
When we designed our flail rear wheel attachment, the aim
was to reduce ground pressure, to reduce compaction and to increase traction.
Adding large floatation wheels to the alpine tractors and
manufacturing bespoke axles for the flails to facilitate floatation tyres that
has reduced the ground pressure by 6.5 psi.
Reducing the air pressure in the tyres also reduces ground
pressure. The flatter the tyre, the
greater the amount of rubber is in contact with the surface. This reduces the overall ground pressure of