What are those dents in I-90 outside Seattle?(boards.straightdope.com) |
What are those dents in I-90 outside Seattle?(boards.straightdope.com) |
It was mislinked on Wikipedia to overpass and while trying to figure out what it should link to I learned that this concept just does not really exist in other countries.
[1]: https://www.waagnerbiro-bridgesystems.com/references/fly-ove...
But this is the advantage of a small country with many people. Good infrastructure.
Concrete is more durable (but it still needs to be maintained) and that is probably why it is used in parts of the U.S. where this is less of an issue. I can't make much comment on what other countries do though I have only noticed concrete roads in the US.
It's bloody awful, like driving over smashed paving slabs. In my big old Range Rover with its off-road air suspension and massive reinforced tyres it's a noisy and uncomfortable couple of miles. In a modern vehicle with ultra-low profile tyres and incredibly stiff "sporty" suspension it must be like being rolled down a hill in old washing machine.
So yeah it's entirely possible that it's a very US thing, I've never seen it anywhere else.
Edit: here you can see a section, with repairs showing up as dark lines across it.
https://www.bing.com/maps?osid=55db8ed6-35d8-4916-82c3-14131...
The only other "web" I do have a small window into is the Japanese language web, thanks to importing cars and car parts, I have been learning Japanese. Web design there is incredibly different, and the approach to social forums like car clubs seems pretty novel too. One thing that transcends the language barrier seems to be information hierarchy which is cool. Parts don't have cars, cars always have parts, small example but that kind of thing.
Driving on concrete roads when I visited the USA was an eye opening experience on just how bad they are for road noise and comfort.
The retrofit begins with cutting of six slots (three in each wheel path) across all transverse joints or cracks. The slots are cut with ganged diamond saws that make six cuts in each wheel path.But yeah, also perfectly possible it's just an error in the article :)
"The dowel bars help extend the life of the pavement by about 10 years or so."
IIRC this is one of the disadvantages of concrete (as opposed to asphalt) road surfaces: it's very hard to repair them in ways that don't degrade over time.
edit: You can tell this road is "real" concrete because of the visible seams between each slab. For an ideal repair, they would have had to replace every affected slab of concrete, which is...all of them along this stretch.
You don't see these concrete road surfaces much near where I live (in Boston), particularly because such roads are much less safe when snow and ice are present.
> I’m not talking about the perpendicular “rumble strips”
They did a really good job installing these. They look like they would be bumpy but I never felt them at all.
Details on how to make a set of dowel-bar-retrofits.
https://dot.ca.gov/programs/construction/construction-manual...
Longitudinal grooving to achieve PIARC category of roughness and rolling resistance of an inverse to raised Cat’s-Eye and Botts’ Dots (“turtles” in Washington/Oregon, “buttons” in Texas). They are reflectorless, and are
https://www.fhwa.dot.gov/pavement/pubs/hif17011.pdf
Not to be confused with Rumble strips which are also known as audible lines, sleepy bumps, wake up calls, growlers, drift lines, waker-uppers and drunk bumps.
A parent of mine who grew up and lived most of their life on the East Coast, US, visited and we drove east across WA. At one point they could not wrap their head around the fact that we had been travelling at around 80 mph for 2 hours. And it basically looked the same out the window :)
The US West is huge.
It's easy to opine for the "internet of old", but I for one do not miss having to post a car problem to a Ford Escort message board and maybe getting an answer after 3 days of being told I am an idiot.
The current repair practice is to pour tar on the asphalt road and then a coating of road gravel. It’s noisey, comes off when heavy vehicles use it, comes off with heavy usage or heavy breaking, comes off in hot sun and it’s utter trash. It’s cheap though!
To my knowledge, it isn't any special application of product. It's literally cheap asphalt they pour on top of cracks and potholes and pound it down lightly. The reason why it's surprisingly smooth is because a thousand plus cars have driven over it, flattening it down to road level.
> "Crews place asphalt and rake it into the pothole. Then they tamp down the asphalt and smooth it out until the road surface is improved. The job takes 15-20 minutes."
They do this because it is literally impossible to get to all of the potholes in spring. Want some neat stats?
https://www.toronto.ca/services-payments/streets-parking-tra...
It's not the most beautiful thing, but it's smooth.
I'm 97.92% sure they don't actually do this because it's better. It's cheaper than resurfacing -- then they drive along with a big machine that grinds off the top few inches of asphalt, crushes it up, adds tar, and puts it back down to be rolled.
It really depends on the car and suspension! In regular car driving over them is fine. In motorhome vibration is so strong that I go in the left lane, otherwise it's two hours of crazy shaking.
I imagine a flyover ramp is more appealing in areas where there isn't a lot of alternate routes available. The US is considerably less dense than Europe so rerouting traffic while a section is closed for major work isn't a big deal. If it's going to last a while, we just pave over a section around the part being worked on.
All of this is super obvious but maybe someone that only speaks english is genuinely interested and hasn't thought about doing it regardless.
Hoping to surpass one of these days.
I don't notice the Discourse one having any trouble searching the whole thread as advertised here though.
Source: have cut concrete it sucks.
Road resurfacing improves stopping distances and rough rides if the road is overall in ok condition. If the road has large cracks in it this does nothing
Tar snakes are used to seal cracks from water because after rain the movement of vehicles over the wet subgrade under the road creates a pumping effect that ejects subgrade material out from the cracks and causes potholes in the future.
In a side note, TN Department of Transportation recently experimented with a more porous asphalt variant on some major roadways, which was supposed to help with drainage. But in the winter, rain soaked deeper into the porous asphalt, causing much larger pot holes than expected. They repaired this with more traditional asphalt, which really stands out next to the more porous type, when it’s raining. I don’t know what the final fix will be, but it seemed odd that they wouldn’t have tested that scenario more fully.
https://boards.straightdope.com/t/what-are-those-dents-in-i-...
I asked someone at WADOT about the very same thing and was told they were to create an irregular surface in one or two of the lanes (notice the street view from down thread they are only in the right most/truck lane) to prevent perfect ice sheets from forming.
Maybe it's both things: they're holes from dowel bar retrofits as their look and placement sure seems to indicate, but they're only visible in one lane because the lane was purposely re- (de-?) surfaced. Or alternatively only the slow lane needed the retrofit at the time it was done just because it carried more of the heavy loads.
Even if I couldn't tell for other reasons, I've seen enough sections replaced for water or gas line maintenance; I've never seen one without concrete, from my side street all the way to the freeway.
(Westall road outside the ikea and Dandenong road in Caulfield where it goes under the train line, if anyone in the know is able to comment)
[1] Or local / devolved authorities etc.
Anything less than airport-grade concrete dies instantly, and then dies again when it invariably freezes to -40° Kelvin, because fuck physics when shit gets cold.
Long haul freight should be done by loading the semi's trailer onto a flat car, and picking it up near the destination.
Another myopic government decision is to try to replace the diesel trucks with electric ones, you know, for the environment. Far better for the environment would be to do away with long haul trucking and use freight trains instead, which are far more efficient. Trains also do not spread tire and brake dust all over the place, either.
Why would they pay property tax on a highway they don’t own?
What they do pay is a per mile tax that is collected at the pump and divided up to the states through IFTA. Every single mile a truck travels is taxed by some state even if it’s just using it for personal use like shopping at Walmart.
That road is nose-to-tail 40-tonne trucks every night, because everything that goes to the north of Scotland from anywhere else in the UK goes up it.
To give you an idea of scale, Scotland has an area about the same as Alabama, but in terms of getting around you'd have to think along the lines of several times bigger than Texas.
There are also a few cities where speed limits drop below a 100 when passing through. That is about health. Specifically noise and fine particles.
None of this is about greenhouse gasses.
I remembered having them a lot in my childhood, but not in recent 10 years. If a road is closed totally there usually something beyond paving going on.
It does rain a good amount in the populated parts of Australia so water shedding is one part, and resistance to temperature changes is another. The myths are true though, it does sometimes melt under high heat and heavy load.
--- google "efficiency of trains vs trucksPS if you like brick roads, there's a big (flat) one out in Redmond I accidently drove on once that someone made a nice post about https://www.dadlogic.net/old-red-brick-road-redmond/
I've actually been out to the Redmond brick road before (on a bicycle -- it was unpleasant).
Funnily enough the Netherlands is also a tax haven but it's only for large megacorporations, not people. They wouldn't be based there at all if it wasn't for the tax benefits so they don't lose out by offering it, they just screw the rest of Europe over by allowing companies to evade taxes in the whole EU.
The other option, making trucks pay their “fair share”, would just get passed along to consumers as higher prices and nothing would change. Like when fuel prices go up, truck drivers don’t eat those costs but they get a higher fuel surcharge which just gets accounted for when they’re pricing the goods on the grocery store shelves.
I also don’t think you fully understand how massively huge the transportation system is in the US. Assuming they could switch over to trains and assuming you live in the Bay Area they’d just have the trains deliver to Tracy or Stockton (where all the big warehouses currently are) and still have trucks deliver to the store down the street. Same amount of trucks you currently see with the only difference being the long haul truckers now doing local work.
Keeping with the Bay Area example, the last three times I delivered there two loads were going overseas out of Oakland and the third was a super small warehouse in San Leandro which didn’t even have a dock and I had to back a half mile down this tiny street — twice because there wasn’t anywhere to turn around and I was originally facing the wrong direction. I deliver to California all the time and all the warehouses are outside of the big cities. Well, except in LA but they’re just generally wrong about most things.
Fatigue damage is the biggest problem. A heavy truck pushes down on the asphalt/concrete, flexing it. Eventually, it cracks and crumbles away. As mentioned elsewhere, fatigue damage goes up as the 4th power of the load.
Railroad tracks are made of steel, and steel flexes nicely without crumbling away. If you stand next to the tracks, you can feel the earth go down as the wheels pass. Steel rails with the load spread out with ties are an effective solution.
Regarding your other comment ("trucks get the goods where they have to go"): in other countries, such as Switzerland, many buildings (think an Ikea store) are required to be reachable by rail, in which case regional trains can deliver goods to a hub, and then local trains can take goods from the hub to the store. No need for trucks in this case.
If you remove bulk freight it’s quite a bit of a difference but still massive.
Much of European freight goes by boat and truck without much train.
I had this job 20 ago delivering for one of the major grocery chains. Southern Nevada, New Mexico and Arizona were all covered out of a single warehouse in Phoenix. That place is a shitshow and that’s with them having a couple hundred docks to unload trucks, lucky to get out of there in seven hours. If they were unloading train cars I couldn’t even imagine how bad it would be. Or the local drivers wasting a whole shift after getting a container out of the train yard.
I also don't see why it would be necessary to revamp the global economy to start using trains more.
And trains are relatively time inefficient so people in Maine couldn’t have their fresh Californian strawberries a couple days after they are plucked out of the field.
Maybe people don’t deserve to have fresh produce but that’s another discussion altogether.
A lot of fresh produce comes in by jet.