I finally stopped to look more closely. These ripples are about 10 inches wide ands look to be almost exactly uniform through long stretches of road. Where does this precision come from?
In: 879
[removed]
I drive about 30,000 miles per year on “Improved Roads” in the Nevada desert for work. I cant speak to the science behind it, but from my anecdotal 10 years of experience it has a lot to do with wheel slippage.
The roads I drive on are mostly just the natural dirt hit with a grader blade to defoliate and level them out. The more problematic areas of caliche and dry lake beds where it floods are improved with gravel taken from the surrounding area.
Every time someone driving on these roads accelerates or stops quickly, their tires slip a little. It may not even be perceptible but all it takes is a little bit of material thrown or pushed either way to create a high spot. You see this mostly in and out of turns where most braking and accelerating occurs. Now every time another tire hits that high spot, it bounces a little and when it hits the ground again, it moves more material. This happens over and over until its a big rutted nasty washboard of a road.
Like someone else said in another comment, washboard roads are uncomfortable so people will move to either side to avoid it and create more washboards.
Another thought I had was that the majority of the traffic on our roads are from solid axle vehicles so a bump on one side of the road can affect the opposing side tire as well
[removed]
Ya hit a bump so ya bump.
But when the bump lands it makes a bit of another bump.
A few cars go by and the 2nd little bump is now a bump that when ya hit it makes ya bump.
But when ya land from the 2nd bump it makes a bit of another bump.
Keep it up and ya got a washboard.
[removed]
[removed]
[removed]
As someone who grew up on a dirt road, these are formed by accelerating, the drive wheels of the car push against the road surface, blacktop doesn’t move, dirt does.
As cars repeatedly drive on the dirt road these get bigger and more of them.
You will notice they only happen and places where you are going to accelerate, like from a stop or coming out of a turn.
When there are enough of them, your tires ride on the tops skipping over the dips.
They are evenly spaced because car’s wheel bases are similar.
[removed]
Washboards on gravel roads are caused by trucks pulling heavy trailers like 5th wheels and toy haulers.
You can see it happen in real time if you ever see them grate the road you will notice its all nice and flat without any washboards. As soon as a truck pulls a heavy trailer up virtually any incline at all that’s where the first signs of washboards appear, they are caused by the torque of the rear wheels spinning out under the heavy load which leaves piles of dirt behind the tires and a shallow rut under the tires.
As more trucks drive the dirt road, especially ones pulling trailers the ruts become more pronounced to the point people start trying to avoid them which just causes them to stretch all the way across the road in many places…
Latest Answers