9 ms·
A little funny to not link to the comment that had the answer — they're dowel bar retrofits. https://en.wikipedia.org/wiki/Dowel_bar_retrofit https://en.wikipe
by mbauman 4y ago
A little funny to not link to the comment that had the answer — they're dowel bar retrofits.
https://en.wikipedia.org/wiki/Dowel_bar_retrofit https://en.wikipedia.org/wiki/Dowel_bar_retrofit
- haunter 4y agoIf a Wikipedia page about a technological topic (so not a person, place etc) has a very few languages available (in this case 2) then it always makes me wonder how other countries in the World solve the same issue. This seems like a very US thing for example but maybe I’m wrong
- Gordonjcp 4y agoThere's one bit of jointed concrete road that I know of in the UK, a few miles where I live on the A90 near Laurencekirk. 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=55db8ed6-35d8-4916-82c3-14131e11a722&cp=56.752882~-2.651094&lvl=18&style=a&v=2&sV=2&form=S00027 https://www.bing.com/maps?osid=55db8ed6-35d8-4916-82c3-14131...
- bombcar 4y agoThe US interstate moves insane numbers of huge ass-trucks that weight one billion metric pounds each or something. 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.
- WalterBright 4y agoThe reason for the interstate trucks is the taxation system that punishes railroads for owning their right-of-way. The trucks cause by far the most damage to the highways, but taxpayers subsidize that with the gas tax. Trucks also do not pay property tax on the highways. 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.
- engineer_22 4y agoTrucks pay much higher tolls. Tolls are based on axles and weight.
- josephcsible 4y agoBut not nearly higher enough. Driving on roads damages them in proportion to the fourth power of per-axle weight, which is about 17,000lbs for a fully loaded semi and 2,000lbs for a car. To put that in perspective, if the toll for the car were $0.25, it'd have to be over $1,300 for the truck for it to be fair in that sense.
- nemo44x 4y agoIt will just raise shipping costs and therefore raise the cost of goods. By charging trucks more it creates a regressive tax effectively. By subsidizing them this is a way we utilize socialism to ensure lower wage people have access.
- WalterBright 4y agoThat's why move the freight by rail.
- fredoralive 4y agoThere’s an interesting blog post about the UK’s unloved and out of fashion concrete Motorways here: https://www.roads.org.uk/blog/diamond-rough https://www.roads.org.uk/blog/diamond-rough which notes that the US seems to occasionally grind the surface of concrete roads, whilst in the UK [INSERT WHATEVER THE HIGHWAYS AGENCY IS CALLED THIS WEEK][1] don’t (barring recent trials) leading to people driving on rough decades old surfaces. Although ISTR it was the expansion joints that were the real annoyance? But I haven’t personally encountered concrete roads in the UK in decades, it’s more of a thing from when I was a kid. [1] Or local / devolved authorities etc.
- wkat4242 4y agoIn the Netherlands we don't use concrete plates. Just asphalt, usually the highly absorbent type. It wears very quickly and ice buildup damages it so it gets replaced a lot. But this is the advantage of a small country with many people. Good infrastructure.
- rocqua 4y agoSadly our bridges don't seem to be doing very well.
- nemo44x 4y agoMany roads are composite here. They have a sub-road made of reenforced concrete that creates a stable layer and then asphalt is laid on top. Because the asphalt wears out it is easily ripped off the concrete layer and repaved.
- rootusrootus 4y agoIn the PNW we commonly use porous asphalt (so the rain doesn't build up and cause hydroplaning) as well. A few interstates still use concrete. I wouldn't be surprised if that had something to do with weather and related maintenance requirements. I-90 being a pretty good example.
- djbusby 4y agoI5 through all of king county is concrete plate. The boundary at Pierce and Snohomish is clear. Odd.
- ehnto 4y agoSame in Australia. Concrete is seldom used, usually asphalt or similar. Lots of patchwork or total resurfacing being done. 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.
- tda 4y agoAnd the best thing: new top layers are applied frequently (sometimes yearly). And they are literally applied overnight: construction starts at 23:00 and is completed before 06:00. And even better, the road isn't even closed. One night they pave the right lane and the next the left lane is paved. Complete road closures for maintenance are exceedingly rare. And if they happen, it will be at night and/or in the weekend. Compared to any place I've been Dutch road infrastructure and maintenance is really on another level. Not just some roads, but pretty much all roads in the entire country are designed and maintained to an entirely adequate baseline (not saying there is no room for improvement, just that the baseline is so much higher than anywhere else).
- the_mitsuhiko 4y agoI was wondering the same thing recently. In Austria and some countries around a pretty popular road replacement system is called "fly over"[1] which has nothing to do with an overpass in the US, but is basically a small bridge put on top of a highway to repair the road surface underneath without interrupting traffic. 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-over-ramp https://www.waagnerbiro-bridgesystems.com/references/fly-ove...
- rootusrootus 4y agoThat's just a way to get traffic off the surface while work is done, though. The dowel bar retrofit is the work itself being done. 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.
- Jorengarenar 4y agoUntil now, I wasn't aware USA makes highways with concrete. As far as I know, in Poland vast majority of paved roads is made with asphalt, rarely bricks.
- HyperSane 4y agoOnly the busiest roads are made with concrete. Most roads are asphalt.
- JoBrad 4y agoIn Middle TN, at least, asphalt is coming back in favor. Apparently concrete doesn’t handle the freeze/thaw cycle very well, and is harder to repair than asphalt. 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.
- rgj 4y agoThat’s porous asphalt, developed in the Netherlands and used on 90% of the roads here. It is fantastic when it’s raining and it gets damaged really quickly when it’s freezing. In our climate the benefits heavily outweigh the downsides and we just apply a new top layer very often (once every 1 - 5 years).
- JoBrad 4y agoThe potholes here were so big that it burst car tires and dented rims. The idea seems great, but not sure why it was so bad here.
- kube-system 4y agoIt depends on the use. Both asphalt and concrete are widely used in the US, depending on the engineering demands.
- goodcanadian 4y agoMy understanding is that concrete is generally not used for highways in Canada because it doesn't hold up well in the yearly freeze-thaw cycle that the majority of the country experiences. Asphalt is used as it is more flexible, and also easier to repair (generally just filling cracks with tar) when the inevitable frost heave damage occurs. 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.
- frogulis 4y agoMostly asphalt here in Melbourne. No freeze-thaw cycle, but anecdotally the few concrete roads I have driven on are pretty rough and the repairs don't appear to be very effective. (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)
- rootusrootus 4y agoMaybe this is true. But honestly, we don't have that many roads in the PNW that are concrete. It was when I lived in the midwest that I noticed them everywhere. I really don't care for them. In the PNW we have relatively few, but the weather here is milder than the midwest. Not sure what that says about the freeze-thaw hypothesis.
- coryrc 4y agoI live in Seattle and almost every single road I drive on is at least concrete base. 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.
- rootusrootus 4y agoMaybe that's a Washington thing, then. In the Portland area it's nearly all asphalt, or asphalt-over-concrete. Concrete is terrible in places where it rains a lot, which is one reason I'm surprised you'd find so much of it in Seattle. We have porous asphalt that never has any standing water even in a downpour. At least when it's maintained, which isn't always a guarantee on some lesser used roads.
- dbetteridge 4y agoAustralia is Asphalt for suburban and urban roads or compacted gravel for the majority of remote roads. 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.
- ehnto 4y agoThe idea that there are "webs" I am simply not privvy too thanks to language excites me for some reason. Even down to those webs having all their own memes and cultural hotspots etc. 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.
- vasco 4y agoIt's not completely inaccessible. If you've ever lived abroad you quickly start using auto-google-translate in Chrome as second nature and finding out which are "the internet places to be" isn't that hard in the first place. Then having lived in about 3 non-english speaking countries I'm sad to report that half the content is ripped out of "English speaking" internet, including memes, but then obviously there's regional culture that varies per website. The subreddit for a specific country + google translate is a good start, but for some countries you'll miss their biggest hangout in reddit (ie: spain with the forocoches forum). That being said you can always Google "top sites by country" and immerse yourself. It's like traveling but for free. All of this is super obvious but maybe someone that only speaks english is genuinely interested and hasn't thought about doing it regardless.
- dang 4y agoThe submitted URL was https://boards.straightdope.com/t/what-are-those-dents-in-i-90-outside-seattle/422061/30 https://boards.straightdope.com/t/what-are-those-dents-in-i-... but our software replaced it with https://boards.straightdope.com/t/what-are-those-dents-in-i-90-outside-seattle/422061?page=2 https://boards.straightdope.com/t/what-are-those-dents-in-i-... because that's what the page says is its canonical URL. I've reverted it now.
- gpvos 4y agoBut the top comment at the /30 URL is not the actual answer either...
- KennyBlanken 4y agoYep. Hilariously it was literally the first reply, which was promptly ignored by everyone. https://boards.straightdope.com/t/what-are-those-dents-in-i-90-outside-seattle/422061/2 https://boards.straightdope.com/t/what-are-those-dents-in-i-...
- mike_d 4y agoBecause the original poster replied in #3 that it wasn't that. 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.
- zerocrates 4y agoSeems awful coincidental that they'd be exactly at the joints between the concrete, as they are in that Street View, if they were added just to make an irregular surface as you say. 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.
- vl 4y agoLooks like filler is gone from these on I-90 because driving in motorhome over them (V-8 F-53 chassis) leads to crazy vibration. Regular car is fine.
- rootusrootus 4y agoThat's interesting, I'd never have guessed. They always seem to be just the right lane, so I figured there must be some other explanation.
- rkagerer 4y agoOn mobile and no time to correct it myself, but I think there's a consistency mistake in that article: 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.
- kelnos 4y agoThe only other explanation I can think of is that the each slot is made with two cuts, each one starting at the crack and moving outward from it. So then the three slots in the wheel path takes six cuts to make (two cuts per slot, outward from the crack). (Or perhaps the opposite; maybe the cuts start away from the crack, and stop at the crack.) But yeah, also perfectly possible it's just an error in the article :)
- gnomewrecker 4y agoEach slot takes two cuts indeed, but the cuts are parallel, one on each “side” of the slot. Source: have cut concrete it sucks.
- rkagerer 4y agoNeat, thanks!