Washboard roads - - okay, 'finally gotta' ask

[Don Becker]

I put this here because we hunters probably run-into (pun intended) these and curse them more than others. What causes this? Is it something with the original preparation of the roadbed? Many, many logging/forest roads don't have this at all. 'Sure can be dangerous in some places.

[gottafish]

looks like Ukia. LOL I think its a slight up grade and you get wheel hope which creats it but I dont know

[baltz526]

china hat rd. should see it when it gets bad.

[TheRogue]

we hunters often are part of the problem...light-ended pickup trucks driving too fast are not good on rocked roads!!

you'll notice it's the worst on sharp uphill corners.

I normally run in 4x4 on all gravel roads, just to avoid it.


TR

[TheTexan]

Harmonics of the vehicles suspension system.

[Uncle ted]

i have been told it is caused by empty log truck trailers but i dont know for sure

[cutt plug]

All the above is true, wheel hops, harmonics of the suspension, empty log truck trailers.

Mostly caused by trucks with light back ends.

4-wheel drive helps to prevent it but unlikely to get that to happen.

Pray for the grader to hit the road prior to hunting season. A freshly graded road is also real easy to cut tracks on!

[Don Becker]

Wow! Quick and great responses. Of course, I figured vehicle traffic had a hand in at least making it worse. Why is it that certain roads don't seem to develop washboard at all, though? Don

[Uncle ted]

some are packed harder? different kinds of soil?

Originally Posted by Don Becker

Wow! Quick and great responses. Of course, I figured vehicle traffic had a hand in at least making it worse. Why is it that certain roads don't seem to develop washboard at all, though? Don

[Mad Mikey]

It's caused by aggressive driving on straight-a-ways, hard braking and/or acceleration on corners.

Where do you usually encounter washboards?

Think about it.

The spots in the road where folks are going to want to speed up quickly, or slow down in a hurry are always the places you hit the washboards.

And, folks drive like maniacs during hunting season, especially near town in the early season when there's still enough light for people who have just gotten off work to make it out for an evening hunt.

Ladd Canyon Road is notorious for this, thankfully it gets re-graded every year or two.

The lower two miles is so bad now I have to creep along at 10mph or less.

[Quaka Wacka]

Originally Posted by gottafish

looks like Ukia. LOL I think its a slight up grade and you get wheel hope which creats it but I dont know

And that wheel hop that it causes only digs out the backside of the bump even more. As mentioned 4wd smooths it out a bit, and helps you maintain control.

[canes_venatici]

Pave all the roads! That will fix it!

[baltz526]

when the base gravel has more clay in it, it packs better and has less washbording. most roads are done with a basic crushed rock or cinders. not a high quality road base

[Jeremy]

Water will enhance the washboard effect as well

[DogZilla15]

Mad Mikey has it right. ABS doesn't help either...

[Eagleclaw]

Mythbuster did a show on washboard roads and they found the faster you drive the less bumby it is... So put the foot to the floor and you'll have a smoother ride

[Northwest Pest]

Mikey has it right.... it is aggressive driving.

[SandyRiverFisher]

Originally Posted by baltz526

china hat rd. should see it when it gets bad.

Oh man, you aint kiddin!

[HntnFsh]

If vehicle operators knew to back off on the throttle when going around corners and up hills.A lot of this problem would be eliminated.

When going up a hill get a little speed up.Gradually ease of the accellerator as you go up.Keeping the back tire from hopping and spinning.Thus causing washboards.

Washboards on hills can be the quick demise of a log truck or dump trucks differential.

The road to my kids house has a pretty steep hill.The people that live on it all accelerate hard going up the hill.Instead of accelerating before they get to it.Then easing off the gas as the y climb.That little stretch of road sucks bad.Bud could easily be remedied if people knew how to properly approach it.

If your not accelerating your wheels wont hop.Even in a light vehicle.

Trailers on gravel roads dont cause the washboards because the tires arent spinning.But once those wash board start.The trailers magnify it because of the bounce of the suspension.Especially on an unloaded trailer.

And yes,roads with good binder in the rock, and a good solid base,resist this a lot better.

[Reel Obsession]

From Askville....

"Washboarding is a process which results in roads (particularly gravel or dirt roads) developing a series of regular bumps with short spacing in the road surface.

According to Tom Pettigrew, a Forest Service engineer, the cause is an unlikely source: your car's suspension. (Well, maybe not yours specifically, but it's not innocent in this matter, either.) A vehicle's suspension system distributes the shock and energy of road irregularities with a bouncing rhythm called harmonic oscillation. At each downstroke, the wheels exert extra force on the road, causing the particles in the road to either pack or displace at regular intervals. Once a pattern of ruts starts to establish itself, it becomes self-reinforcing due to what engineers call forced oscillation. The next car hits the same irregularities in the road and bounces at the same rate, causing the pattern to become more and more defined. Forced oscillation overcomes minor variations in oscillation rate that might otherwise arise due to differences in car weight.

Wouldn't variations in speed affect the washboard pattern? Sure, which brings us to another critical part of the feedback loop: you, the driver. Drive too fast on a washboard road and the downstroke exerted by the car wheels may meet the road at a point where a bump is ramping upwards. You know what that means: You bounce off the ceiling. Instinctively most drivers slow to a speed at which the downstrokes coincide with the troughs between bumps, reinforcing the pattern.

Washboarding is inevitable in any unpaved road that sees fairly heavy traffic however are typically created by overly soft road subsurface materials. . The only way to avoid it is to: (a) radically redesign how automotive suspensions are made, (b) give up suspensions altogether, or (c) keep off those dirt roads."

So it sounds as if some road surfaces are much more suseptible to washboarding than other roads surfaces.

[Don Becker]

Originally Posted by Reel Obsession

From Askville....

"Washboarding is a process which results in roads (particularly gravel or dirt roads) developing a series of regular bumps with short spacing in the road surface.

According to Tom Pettigrew, a Forest Service engineer, the cause is an unlikely source: your car's suspension. (Well, maybe not yours specifically, but it's not innocent in this matter, either.) A vehicle's suspension system distributes the shock and energy of road irregularities with a bouncing rhythm called harmonic oscillation. At each downstroke, the wheels exert extra force on the road, causing the particles in the road to either pack or displace at regular intervals. Once a pattern of ruts starts to establish itself, it becomes self-reinforcing due to what engineers call forced oscillation. The next car hits the same irregularities in the road and bounces at the same rate, causing the pattern to become more and more defined. Forced oscillation overcomes minor variations in oscillation rate that might otherwise arise due to differences in car weight.

Wouldn't variations in speed affect the washboard pattern? Sure, which brings us to another critical part of the feedback loop: you, the driver. Drive too fast on a washboard road and the downstroke exerted by the car wheels may meet the road at a point where a bump is ramping upwards. You know what that means: You bounce off the ceiling. Instinctively most drivers slow to a speed at which the downstrokes coincide with the troughs between bumps, reinforcing the pattern.

Washboarding is inevitable in any unpaved road that sees fairly heavy traffic however are typically created by overly soft road subsurface materials. . The only way to avoid it is to: (a) radically redesign how automotive suspensions are made, (b) give up suspensions altogether, or (c) keep off those dirt roads."

So it sounds as if some road surfaces are much more suseptible to washboarding than other roads surfaces.

Hey, 'pretty-much say's we've all got it right . . .

Originally Posted by Eagleclaw

Mythbuster did a show on washboard roads and they found the faster you drive the less bumby it is... So put the foot to the floor and you'll have a smoother ride

I sure hope that isn't taken too seriously - - - yea, it smooths-out the ride until you lose control and kill yourself.

Don

[jokester]

Originally Posted by TheRogue

I normally run in 4x4 on all gravel roads, just to avoid it.


TR

I do the same on gravel roads. Helps keep from tearing up the roads, plus it engages my 4WD which usually doesn't happen too often living in the city

-jokester

[nakoa]

i starts when the loggers move their trscked equipment and then log trucks empty ot loaded use there jake brakes followed but pick ups and cars driving to fast. i will always put my truck i 4 wheel drive when i am going up a hill it helps some. and i am not point a finger at the loggers. i just learned this when i drove log trucks.

[rem721]

China hat is bad but the 23 road past pine mt. is the worst i've ever seen.

[Flatfish]

Depending on the vehicle, China Hat is best traveed at 40-50 mph. Get on top of it, and it aint as bad.