|
Wi | I thinK I saw one from Purdue that had a lot of the same data/info.
IIRC topsoil compaction (up to 12" depth IIRC) was a result of tire pressure exerted on the ground so you could reduce topsoil compaction with better flotation regardless of axle load. This compaction can also be easily removed. Subsonic compaction (over 20"depth IIRC) was a result of axle load only and no amount of flotation would change that. They also said that normal freeze thaw cycles did little to remove it. The space between those two was a combination of axle load and tire pressure.
Plow layers also played into the compaction issue. They acted as a barrier and reduced the amount of compaction that was able to get past them.
They showed tires inflated to 6psi compared to tracks both on 8000 series Deeres. Both were able to produce up to 18psi on the ground in certain spots. They said that even though the tracks contact patch is larger, it still has pressure points where the wheels are and soil dwell time is longer than with a tire which can lead to more compaction. I remember them saying generally the pressure exerted on the topsoil in a radial is 2psi higher than the inflation pressure. It's important to note though that the pressure from radials is much higher near the sidewalls versus Bias which carry the load in the center.
It's interesting data to say the least but like anything its really all in how you interpret it and apply it to your conditions. Obviously soil type and condition plays the biggest role and it's impossible for studies to test every variable. The real test is in your own fields and what you see. The main thing to take away from the research is how to test it equally and what to look at.
I tthink tires can compete with tracks however the issue is their size. They have a much wider footprint which can be an issue at times . If you are doing controlled traffic/tram lines you could argue that a track compacts much narrower area. The people getting the same flotation as tracks are often running dual 710s or dual 800s. That's 5' of tire on each side plus a foot or so between the duals so 6' or so versus 3' for the track.
If I had a lot of time money and a soil box I'd love to test it. But I don't. The research center for our university is down the road though. | |
|
Compaction - Tires vs. Tracks
