Location: Outside U.S.
Country: South Africa
Date: Spring 2013
What are corrugations and how can corrugations on a gravel road be neutralized?
Here is a picture of corrugated metal. This is a means to add definition to the word corrugated:
A corrugated road has these periodic bumps in it giving the appearance (and feel) of driving over an old washboard.
A corrugated road can be repaired by reworking the surface of the road to smooth it out either with shovels, picks, farm plows, or heavy equipment such as a road grader:
Many readers may not be familiar with corrugations. Corrugations occur on a roadbed. The details depend upon the on soil mechanics and the suspension of the vehicle, but the end effect is a ?washboard? effect. The ?high? places get ?higher and higher? while the ?low? places get ?deeper and deep?. You can find web sites that discuss the washboard effect, but I am not sure that the exact mechanism is well understood.
Thanks for the quesiton. By "corrugations", do you refer to washboards or cuts in the pavement by the side of the road? Washboards are formed by erosion of dirt by water. After the water erodes the dirt, the dirt dries up from the Sun's heat and becomes hard and packed.
There are often cuts in the pavement by the sides of roads. When you drive over these cuts, the tires make a distinct sound which alerts the driver that he or she is going off the road.
I hope this helps. Please let me know if you have more questions.
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Update: November 2011