How Truck Escape Ramps Stop Out-Of-Control Big Wheelers

How Truck Escape Ramps Stop Out-Of-Control Big Wheelers


Oh! He took it! He took it, dude! Gravel is flying! Dirt is flying! Narrator: If you’ve driven any one of the many highways
crisscrossing the world, chances are you’ve seen one of these: a truck escape ramp. Some escape ramps slope upwards. Others are flat. Some contain sand, others gravel. But regardless of design,
they all serve one purpose: to bring vehicles with
malfunctioning brakes to a safe stop. Just how do they work? When designing a new
ramp, state authorities consider factors specific to the road, like how steep the grade
is and what road conditions look like at the bottom of a hill. Though they may look different depending on where you see them, escape ramps around the world
do have some things in common. Most escape ramps make
use of arrester beds, pools of sand or gravel. The material in the bed is selected for their low coefficients
of interparticle friction, meaning when a wheel or
axle touches the bed, the material in it moves
away from each other, allowing the truck to sink into the gaps. Like a swimming pool, escape
ramps are shallow at entry, anywhere from 3 inches
deep, and get deeper, to around 48 inches at 100 to 200 feet in. When a truck enters the bed, it meets little resistance at first, then more as it travels. This means the truck
decelerates gradually, reducing the risk of injury to the driver, and stands less risk of
flipping over, or capsizing. When observing escape
ramps around the world, three designs stand out: the sandpile bed, the gravity escape ramp, and the mechanical arrester ramp. This is a sandpile bed. This type of escape ramp
contains loose rows of sand perpendicular to the direction of traffic. As a truck collides with the pile, the energy of the truck is
transferred to the sand. As the sand is sent flying
away at high speeds, an equal and opposite force
acts against the truck, reducing its velocity. Impacting sandpiles, though, is… jarring, putting the driver at
higher risk of injury, which brings us to the
gravity escape ramp, distinguishable by its
gradually ascending slope. In addition to the friction
of material in the bed, gravity works on the truck,
pushing it down and back. The sloped gravity ramp is more effective than a flat arrester bed. A 10% grade could allow a truck to halt anywhere up to 85 feet sooner. Gravity ramps are the most cost-effective where natural rises occur
adjacent to the road. Some terrains, though, simply do not allow for a naturally occurring
gravity escape ramp. So, state agencies have turned to a more experimental
form of escape ramp. The mechanical arrester ramp
can be installed on flat ground or even downward slopes. Unlike other designs, this ramp does not have an arrester bed. Instead, it contains a series
of stainless-steel catch nets. The nets absorb the energy
from a truck collision. Like a rubber band being pulled taut, the force exerted on the
truck increases exponentially the further the truck travels. The mechanical arrester
ramp then can stop a truck more quickly than gravel
or sand arrester beds. Entering a truck escape
ramp is a one-way trip. If the ramp works properly, a truck will either end
up submerged or damaged, needing a tow to recover. Despite the expense,
agencies urge truck drivers and other motorists to
use the escape ramps.

About the Author: Michael Flood

100 Comments

  1. With Business Insider’s recent videos, I’m surprised they didn’t try to squeeze in race & gender into this.

  2. I needed this back when I used to ride my bicycle down the hill and couldn't stop.
    🤗🤗🤗🤗🤗🤗🤗🤗🤗🤗🤗

  3. So its true.. these ramps are here for people to escape the cops when being chased.. no wonder why there's random ramps on the side of roads in games they got it from real life!!

  4. I honestly didn't particularly like the cut out representation of what you were trying to do. I would possibly even not make it so jumbled. Looking at the rock piles and sand piles with your cut outside made me kinda loose track and what you were saying. Sorry I didn't like this video and hope it helps your next one

  5. on the lewsiton grade Idaho they have lots of ramps one of the the ramp was frozen and just became a launching jump. for the truck was caring sheet metal and just slicked threw everything upon landing … kind of sad, then another issue where the trucker could not get to the ramp because of a school bus was in the way of the last ramp and the truck went the other way and flipped killing everyone in the truck my friend was in the school bus. it was horrific for them.. this is a serious issue for rookie drivers and exsperenced drivers, big load on long steep grades will not slow down with brakes, best to never get speed use low gearing…

  6. Thanks for the info. My family had our first road trip west of BC and as I noticed multiple dirt roads along the side freeway that goes way up vertical, and I wonder what were those for. Why put up dirt roads with no other vehicles would go up there in the first place? This video just answered it for me.

  7. In India people would start selling fast food on it! Thankfully we don't have them.. also, this is the first time I'm hearing about such a thing!

  8. This is the first I hear of these. Any in Canada? Really neat stuff… Sucks that there's no way to stop a runaway truck mechanically or electronically in 2019 though… :/

  9. They mostly exist on mountainous express ways. There's 3 on one strip of expressway here because a lot of people have died due to trucks losing brakes when going downhill. Seen cars and trucks go on them too and they just sink and stop.

  10. Wouldn’t the gravity one just have the trucks roll back down or is there something stopping them from doing that

  11. I wonder why they don't use water and a long pool that gradually get deeper? This is how they stop super fast rockets that are being tested.

  12. Gear down and use the engine brake. No brakes needed. I don't understand how guys have brake failures on mountains. I hardly ever touch my brakes.

  13. Drivers scared to use them because of the fines. Can this narrator sound anymore like a girl? Must be a JB HUNT driver.

  14. Everything goes up will go down so I don’t thing thing the ramp would be that good if you lose your brake cus the trailer will ended up going backwards and hit cars, that new wires thing is kinda smart, similar to the one they use on carriers to stop jets

  15. Ahhhh now I know what that ramp is for on the part of a freeway i always take which is down hill. I always wondered what the random ramp is for lol.

  16. In Ohio they're not sand or gravel, it's just a ramp going up and it has an exit on the other side, looks just like an exit/entrance ramp setup.

  17. Truck: Brakes stop working
    Gravity Escape Ramp: Hi 👋
    Truck: reaches top of escape ramp
    Truck driver: Phew 😅
    Truck: starts falling back down the ramp…

  18. The escape ramp you showed at 0:51 isn't in Lavant, Austria it is in Hann. Münden in Germany it is the Werratal-bridge, which you can see on the backround.

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