[HN Gopher] What are those dents in I-90 outside Seattle? ___________________________________________________________________ What are those dents in I-90 outside Seattle? Author : haossr Score : 69 points Date : 2022-12-30 19:32 UTC (3 hours ago) (HTM) web link (boards.straightdope.com) (TXT) w3m dump (boards.straightdope.com) | landr0id wrote: | I asked the WSDOT the same question a while back: | https://twitter.com/landaire/status/944698354742599681 | | "The dowel bars help extend the life of the pavement by about 10 | years or so." | idatum wrote: | Only slightly related, about I-90 generally: | | 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. | rootusrootus wrote: | There are a number of areas out in eastern Washington where the | state patrol doesn't often bother with speed enforcement and | people routinely go even faster. It is common to have packs of | cars going up the left lane over Manastash Ridge at closer to | 100 mph. With a closure rate of about 70 mph on the trucks in | the right lane. One way to make an otherwise monotonous drive | more interesting. | jasonhansel wrote: | > Maybe they didn't use the best grout and that's wearing away | faster than the surrounding concrete. | | 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. | egberts1 wrote: | Dowel Bar retrofit. | | 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. | unixhero wrote: | A forum! How refreshing. | quickthrower2 wrote: | Looks like a discourse.org one | legitster wrote: | Man, reading this format does not make me miss forums. | | 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. | lostlogin wrote: | Now you can get that response in minutes or even seconds, and | in a more readable format with push notifications and | advertising. | [deleted] | osti wrote: | I always thought it was to help with traction during winter... | They are only present outside the city afaik. | dbavaria wrote: | They're present in the city too, here are some in Seattle: | | https://maps.app.goo.gl/2j5H4gEXKrRVFr469 | modeless wrote: | I haven't seen these in a decade but I knew what they were | talking about instantly. I used to wonder what they were all the | time. I sure didn't expect to get an answer randomly on the HN | front page. | | They did a really good job installing these. They look like they | would be bumpy but I never felt them at all. | vl wrote: | >They did a really good job installing these. | | 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. | modeless wrote: | This was a decade ago. Perhaps the replacement concrete is | wearing away now. | frosted-flakes wrote: | Similarly, I'm always impressed by how smooth the ashpalt | highways in Toronto are, even though they are spiderwebbed with | cracks absolutely everywhere. That's because the cracks are | filled each spring with some sort of sealant. They make a | regular slapping sound as the tires pass over them, but cannot | be felt. | lostlogin wrote: | I don't think you could do the repair with asphalt. I'm not | even sure I've ever driven on a concrete road, as down here | in New Zealand there aren't any I don't think. | | 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! | frosted-flakes wrote: | Of course they don't add rebar to asphalt roads, that would | be ridiculous. The sealant process is done manually, with | some poor sod pushing a machine along each crack and | injecting hot sealant which prevents further water | incursion and the associated frost heave. That's partly why | I'm so fascinated with it: some sections of highway are | cracked _everywhere_ , with hardly a square metre that | doesn't have a crack running through it, and yet they're | extremely smooth. | LegitShady wrote: | you are describing an asphalt microseal over the entire | road surface. they are describing sealing of cracks using | asphalt "tar snakes". They address different problems. | | 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. | Maursault wrote: | I don't understand how everyone knows what the commenter is | referring to when it took me forever. I figured he was referring | to the "dents" on the shoulder, which I thought were rumble | strips. | fckgw wrote: | If you scroll up to the top of the thread the OP posted a | little ASCII diagram of what they were describing | mbauman wrote: | 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 | haunter wrote: | If 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 | the_mitsuhiko wrote: | I 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-ove... | goodcanadian wrote: | My 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. | rootusrootus wrote: | Maybe 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. | frogulis wrote: | Mostly 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) | Jorengarenar wrote: | Until 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. | rootusrootus wrote: | The vast majority of paved roads in the US are asphalt. | HyperSane wrote: | Only the busiest roads are made with concrete. Most roads | are asphalt. | JoBrad wrote: | In 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. | kube-system wrote: | It depends on the use. Both asphalt and concrete are widely | used in the US, depending on the engineering demands. | voidfunc wrote: | Depends where in the USA you are. Most of the Northeast is | asphalt. | garaetjjte wrote: | Some highways (eg. east part of A2) in Poland are concrete | too. (not to mention post-German concrete highways, but I | think they are already gone) | wkat4242 wrote: | In 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. | nemo44x wrote: | Many 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 wrote: | In 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. | Gordonjcp wrote: | There'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=55db8ed6-35d8-4916-82c3-14131. | .. | bombcar wrote: | The 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 -40deg | Kelvin, because fuck physics when shit gets cold. | Ancalagon wrote: | I love the hyperbole in this comment! :D | usrusr wrote: | Allow me to single out the metric pound, which is defined | as precisely a billionth of the weight the local road | surface can withstand. Noteworthy for being one of the | few units that work for both mass and weight because the | local gravity is conveniently factored in. | WalterBright wrote: | The 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. | nemo44x wrote: | The USA has possibly the best freight rail system in the | world and it's used extensively. Trucks pay a ton of | tolls, licenses, and fuel tax. | engineer_22 wrote: | Trucks pay much higher tolls. Tolls are based on axles | and weight. | josephcsible wrote: | But 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 wrote: | It 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. | fredoralive wrote: | There'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 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. | dang wrote: | The submitted URL was 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-... | because that's what the page says is its canonical URL. I've | reverted it now. | gpvos wrote: | But the top comment at the /30 URL is not the actual answer | either... | vl wrote: | Looks 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 wrote: | That'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. | insane_dreamer wrote: | I didn't know what purpose they served but I can tell you they | are nasty if you hit them with their bike at speed; almost had a | serious accident when moving out of the lane and over to the | narrow shoulder to let cars by me pass (this was on a small | 2-lane road through a pass, not a highway of course), didn't | realize how deep the dents were and almost lost control of my | bike ___________________________________________________________________ (page generated 2022-12-30 23:00 UTC)