what creates corragations

Hi

Been discussed before, several times I think. Do a forum search (while youre waiting for "new" posts on the subject:)

Cheers
Greg

John

came across this on google...........ripples in the road

As to how to best deal with corrugations - reduce tyre pressure (say 20-25% below bitumen pressure) and drop your speed by at least the same amount. Its a matter of trial and error until you find what suits you and the road conditions.

Have you observed that different road surfaces will have different corrugations in terms of height and distance between crests.

Enjoy the GRR

Cheers

An then there are potholes....

I have found that riding a mountain bike along a corrugated road it seems to be better on the right hand side.... not necessarily safer, but more comfortable.

Every so often on a long stretch of rippled road I have tried this out with a car 4wd... makes not much difference!

BAD IDEAS.
4x4s driving in 2WD.
Tyre pressures too high.
Speed too high.
Low profile tyres.

Cheers,
Peter
OKA196 Motorhome

There are no straight lines in nature. The natural state of a road is to have corrugations. So your question should be:
"What doesn't cause corrugations?"
A: The grader.

There are links on the internet about this.
Basically the theory is that it begins with natural small indents in the dirt road and as the wheel drops into it it deepens the corrugation. As the wheel then rebounds it creates the rise. As the wheel drops again it creates the next indent. This continues on and on.

They're worsened by high tyre pressures, 2wd and high speeds creating wheel spin when the drive wheel is momentarily in the air and ripping into the crest of the corrugation when the drive wheel lands again.

Ways to make driving better:
reduce tyre pressure about 20%
use high range 4wd, NOT 2wd
slow down a bit, it's not a race
do your slowing down before a corner and slowly accelerate through corners allowing the front wheels to pull you in the right direction
make sure you have good shockers and take a spare for front and rear

Corregations are the natural state of the road....flat is not natural and all road surfaces are on a constant evolution back to corregations.

Look at desert sands...corregated...look at the ocean floor...corregated.

Drive on the Hume Hwy into Sydney...the concrete sections are corregated just at a lowert fequency of dirt. Ie the harder the surface the lower the Freq of the waves and the longer it takes to form them.

Dr Karl has written a few articles on the subject...Google him.

Matt.

Any road surface without sufficient binder will corrugate. Vehicle speed, Tyre pressures, driver styles all combine to determine the severity.

Roads that are never maintained, do not have binder material occurring naturally and a wet season to aid in compaction are corrugations mine fields :-)

We have tried to repair sandy sections of road in the cape (that always corrugated) by mixing with imported gravel, failure was always a matter of time once the binder was worn from the surface.

The only way to fix these roads is to form from local material and sheet in a good roadbase.

;-) Now the locals way to beat it is to be the fastest on the road so your ride on top of the corrugations :-) The tourist way is as slow as you need to go to not shake your teeth out.

Cheers Tony