98 comments

  • atourgates 4 days ago ago

    In a somewhat related practice, some roads in the Tour de France this year have been painted with "white shit" (rider Tom Pidcock's words) in order to combat the asphalt melting in the heat, with the unfortunate side-effect that it seems to be slippery and several riders (including Tom Pidcock) crashed going around a corner when the lost traction.

    Coverage here: https://velo.outsideonline.com/road/road-racing/tour-de-fran...

    But of course, this was done in response to past serious crashes that occured because the asphalt melted. So, it's sort of a damned if you do damned if you dont scenario for the organizers.

    • Animats 3 days ago ago

      Pepe's Towing in Los Angeles reports asphalt collapses where loaded semitrailers are parked with the landing gear down. On hot days the concentrated load of the landing gear sometimes punches through the asphalt.[1]

      This is why truck dock areas are usually paved with concrete.

      [1] https://www.youtube.com/watch?v=LBrULmCGJfc

      • jordanb 3 days ago ago

        Years ago Chicago started putting concrete pads on the road at bus stops because the busses stopping in the exact same spot repeatedly was carving ruts into the asphalt.

        • superb_dev 3 days ago ago

          A city I used to live in did the same thing when they refurbished all the major bus stops. I always wondered why

          • bombcar 3 days ago ago

            Also if a vehicle is stopped and the driver turns the wheel (with power steering this isn't hard) - it will eventually drill holes in asphalt - you can sometimes see this in house driveways where someone turns around.

          • toasty228 3 days ago ago

            You can even see the asphalt "waves" pushed by the buses stopping here over and over again

        • cwillu 3 days ago ago

          Yeah, my city is currently going through every bus stop in the city, redoing the pavement in concrete. Construction season has been nasty for us this year :p

      • andrewflnr 3 days ago ago

        Motorcycle riders also report their sidestands sinking into asphalt on very hot days, to the extent that many of them carry some kind of wide weight-spreading thing to put under the stand. Apparently a face plate (?) for an electrical junction box works great.

        • pacbard 3 days ago ago

          Usually, a crushed soda can is good enough to prevent the kickstand to sync in the pavement. You can usually find a can in a random parking lot. That, or find a strip of concrete. That's why sometimes motorcycle park on the sidewalk in front of big box stores on a hot day.

          • MrMember 3 days ago ago

            Yep, I use a soda can and have never had any issues.

        • esseph 3 days ago ago

          My bicycle did this as kid in the summer

      • 3 days ago ago
        [deleted]
    • Dah00n 3 days ago ago

      This isn't a new thing in the Tour and it is normally not a problem, but since someone crashed on it then it must be the "white shit" that caused it. Not one of the hundreds of other variables - like the rider.

      • atourgates 18 hours ago ago

        Several riders independently crashed in the exact same spot, including Pidcock who is a famously good descender.

        These are literally world class professionals at riding their bikes downhill around corners without crashing. If they say the white shit caused the roads to behave differently than they expected, I'm going to believe them.

      • throw1234567891 3 days ago ago

        Paint is usually slippery. There are special standards for how slippery a paint painted on the tarmac can be. But it’s calculated for cars, not racing bicycles with teeny-weeny tires. Could have been easily the paint.

        • NetMageSCW 2 days ago ago

          Perhaps they should have used some type of traction paint.

          • throw1234567891 2 days ago ago

            There are other problems with that in wet conditions.

        • olyjohn 3 days ago ago

          I mean, one of the first things they teach in motorcycle safety classes is that the road stripes are slippery and could cause a crash, especially in the rain. Even if there us a standard for how slippery it can be, it still doesn't match the traction of the road surface.

    • thaumasiotes 3 days ago ago

      > But of course, this was done in response to past serious crashes that occurred because the asphalt melted. So, it's sort of a damned if you do damned if you don't scenario for the organizers.

      Well, not entirely. You always have the option of repaving the roads with cobblestone or something.

      • subscribed 2 days ago ago

        Cobblestones?

        They're very slippery when dirty or wet. Seems like a much worse option.

      • albumen 3 days ago ago

        Or just have the cyclists use fatter tyres.

        • dgoldstein0 3 days ago ago

          That would also require fatter wheels. Which together have higher moment of inertia which makes for slower bikes (as more energy is required to get the wheels to the same speed).

          Not exactly what people want in a race.

          • adrianN 3 days ago ago

            You can buy faster bikes than what is allowed at the Tour, so the only concern would be making records incomparable.

          • Dah00n 3 days ago ago

            And yet fatter tyres are faster than the slimmer ones they used to run. No-one run slim tyres these days.

            • webnrrd2k 3 days ago ago

              I could be wrong, but it turns out that somewhat fatter tires with lower pressure are faster because less energy is wasted by deforming slightly and rolling over small bumps, as opposed to thin high-pressure tire "bouncing" over pavement. There is less wasted vertical motion with the wider tires.

          • baq 3 days ago ago

            Fatter wheel is better than a dnf right?

            • throw1234567891 3 days ago ago

              Not really. If you finish second, you are the first to lose.

    • Wowfunhappy 3 days ago ago

      ...I know absolutely nothing about competitive cycling, but it occurs to me:

      1. Would the Tour de France have been rescheduled if it was raining that day?

      2. If the answer to #1 is no, is the paint any more slippery than water would have been?

      3. If the answer to #1 is yes, then they should also reschedule for extreme heat.

      • atourgates 18 hours ago ago

        1. No, they ride in the rain all the time.

        2. It's not so much that the white shit (actually lime) is slippery, it's that it's unexpectedly slippery. Riders are generally quite good at going the right speed for the conditions. This just a new and unexpected condition they don't have experience with yet.

        3. They did shorten one stage because of extreme heat, and there has been talk about rescheduling (both in terms of season, and moving the races into cooler parts fo the day), but the Tour is pretty tradition bound, so it'd take something quite exceptional to see that happen.

  • amiga386 3 days ago ago

    At least they're doing something.

    I couldn't believe the state of US railtrack:

    https://www.youtube.com/watch?v=9X2A2f6E5DI

    Just go slower! We don't want to pay for maintenance. What's the worst that could happen? You derail and your toxic payload catches fire and poisons the neighbourhood?

    https://en.wikipedia.org/wiki/East_Palestine,_Ohio,_train_de...

    • pixl97 3 days ago ago

      Maintenance is expensive, profits are now!

      • euroderf 3 days ago ago

        A new mantra for Wall Street.

      • edoceo 3 days ago ago

        I hate that you are both correct.

    • kmeisthax 3 days ago ago

      It's funny you mention that, since I mentally associate Union Pacific with the worst of US rail disinvestment. They're the ones that were patient zero for the "precision scheduled railroading" brainworm that led all our railroads to downgrade track and lengthen trains to insane lengths[1]. Or at the very least, they were at the top of Amtrak's delay-shaming list until a few years ago[0] when they somehow improved???

      ...anyway, I'm now genuinely wondering how the hell rail in such an awful state can still maintain the correct gauge for trains to run on!?

      [0] https://www.amtrak.com/content/dam/projects/dotcom/english/p...

      [1] Salt Lake City is trisected by Union Pacific freight rail. We have some of the largest city blocks in North America, but they're still not long enough to avoid a single stopped Union Pacific train blocking multiple crossings for hours on end. If you want to really, REALLY hate trains, move to the west side of SLC.

      Also, talk to your politician about the Rio Grande Plan.

  • warumdarum 3 days ago ago

    This of course beeing the effect of seemlessly welded together rail with nowhere to go..

    • jimnotgym 3 days ago ago

      Indeed. Didn't they used to have expansion gaps?

      • cgyvbunji 3 days ago ago

        They did. It's what caused the click-clack sound trains used to have, and the change to continuous welded rail is why there is no click-clack anymore.

  • kylehotchkiss 3 days ago ago

    I love a simple solution to billion dollar problems

    • conorcleary 3 days ago ago

      ...that will be done for a few years, dwindling quality and measurement, lack of continuous data collection, or sparse, which loses 'track' of performance and effect. Then, lots of subcontractors will use the wrong paint (maybe a black market appears), incorrect application, too thick too thin on top instead of the sides... more derailments start occuring because the whole program gets used to boost stock price and try to get fed contracts instead of actually engineering a solution and maintaining it as protocol.

      Lots of major industrial specialty paint manufacturers and white labelers are publicly traded, owned by BR & VG.

  • elric 3 days ago ago

    I'm surprised that this is as effective as the numbers suggest. I would have thought steel rails would be pretty good at reflecting/radiating heat. TIL.

    • GuB-42 3 days ago ago

      Reflecting and radiating heat are mutually exclusive, and if some material is good at radiating heat, it is also good at absorbing heat, otherwise it would violate the laws of thermodynamics.

      It is a bit more complicated than that because light come in different wavelength, but it is the general idea.

      Railroad rails tend to be dark except for the polished top surface, so they absorb/radiate the heat more than they reflect it. Painting them white changes that, it makes them less effective at radiating their own heat, but because they don't produce much heat by themselves, it is not a big effect, but it also makes them less effective at absorbing the heat from the sun, a much greater effect, so, the rails get cooler overall.

  • tiagod 3 days ago ago

    "That’s huge. If you’re not fighting the sun’s heat, you dramatically reduce the risk of the rail shifting.”

    Am I misreading or does this say the opposite of what they meant?

    • adrianmonk 3 days ago ago

      I think the safety officer meant that white paint prevents the rail from heating up. The heating of rails contributes to problems with derailment. If the heat isn't a contributor, that heat is one less thing you have to fight (as in account for).

      But the photo caption paraphrases him and says that the white paint fights (as in prevents) the heat, which uses similar words but a different logic to it (but the same overall meaning).

      If I've got that right, then I think the blame lies on whoever wrote this article for making it confusing.

    • toast0 3 days ago ago

      Reflecting the sun means the rail no longer has to fight the sun's heat.

      Without the paint, the sun heats the rail and heat expansion fights against the elements holding the rail in place until the rail cools down or something moves. If the something moves, trains can derail.

    • earth-tattoo 3 days ago ago

      You are misreading. Basically the white paint is "fighting the sun's heat".

      • foxglacier 3 days ago ago

        But that's backwards. I took it to mean the rails or the engineers are no longer fighting (coping with) heat input from the sun because the rail never receives that heat when it's reflected away by the paint.

        • conorcleary 3 days ago ago

          It means the paint is fighting the energy conversion potential encroaching on the steel, in place of the steel fighting it with no covering or shield

          • foxglacier a day ago ago

            I know what it means. "you're not fighting the sun's heat" means "the paint is fighting the sun's heat" but that's no explanation of how it could mean that. I say it's backwards because clearly whatever's doing the fighting is not the paint because it has the opposite effect. It must be the steel, as you say, or the people struggling with the problem.

    • conorcleary 3 days ago ago

      Fighting like a verb I think

  • DaiPlusPlus 3 days ago ago

    > “When people first saw it, they said, ‘Why haven’t we been doing this for a hundred years?’” Doerr said. “That’s the kind of question I love to hear, because it means the culture of safety innovation is alive and well.”

    Union Pacific haven’t been doing this precisely because they don’t have a culture of innovation…

    • mark-r 3 days ago ago

      The question applies more broadly than Union Pacific. Why hasn't this been an industry standard for 100 years?

      • DaiPlusPlus 2 days ago ago

        > Why hasn't this been an industry standard for 100 years?

        Because the US heavy rail system is a duopoly with no incentive to innovate.

  • gattilorenz 3 days ago ago

    According to the Dutch railway maintainer, it's not needed there, and the effect is not really proven: https://www.prorail.nl/veelgestelde-vragen/zomer/waarom-zijn...

    Same for the Swiss, according to the natioanl railway company the results of their tests were “inconclusive”, but other operators of the Swiss network say that it depends on the exposure and other factors (but the challenge is keeping them clean, in a week they are already too dirty). https://www.rsi.ch/info/svizzera/I-binari-sbiancati-non-serv...

    • OptionOfT 3 days ago ago

      Sorry, but both Switserland and definitly the Netherlands are further North vs a significant percentage of the USA.

      Bern, Switzerland is very close to the same latitude as Quebec City, CA or Fargo, ND, USA.

      The Netherlands is even further North. Due to the lower angle of the sun hitting them they might get completely different results vs here in the South-Western USA.

      Also weird in the article:

      > Het aanbrengen is behoorlijk arbeidsintensief.

      Really? How is driving a machine over the rail labor-intensive?

      • moi2388 2 days ago ago

        Because there is a lot of rail. And it requires inspection.

  • londons_explore 3 days ago ago

    Hopefully they have a sandblaster mounted to the same train to clean the rails first, else they're gonna have to do this again every year...

    • olyjohn 3 days ago ago

      Or they have a heavy rust converter (phosphoric acid?) built into it. Similar to a self-etching primer.

  • Havoc 3 days ago ago

    20 degree drop. That’s crazy

  • dupontcyborg 3 days ago ago

    this isn’t the point of the story, but is that paint truck driving on the railroad tracks?

    • LarsAlereon 3 days ago ago

      Yes, they're called "high-rail" or "road-rail" vehicles. They have rail wheels that can be lowered down to drive on tracks or raised up for road use.

      • edoceo 3 days ago ago

        And sometimes the axel is short (narrow), so the tires are on the rail. It's funny to see them on a standard road.

  • jeffrallen 3 days ago ago

    Practical Engineering already explained the correct solution to this problem:

    https://youtu.be/zqmOSMAtadc?si=UUlmnk9sI-leq0SV

    But of course, American infrastructure was built on the cheap, and is not maintained correctly. This is why we can't have nice things.

    • anonymars 3 days ago ago

      Why couldn't this also help with continuous-welded rail?

      Your own video points out that it's still prone to trade-offs: rail breaks in the cold are better than buckling in the heat, but what if you could reduce the high point with white paint so you could expand the practical temperature range?

      • brookst 3 days ago ago

        Or paint that turns black at low temp and white at higher temp?

        • HappMacDonald 11 hours ago ago

          This is what I want on my house and my car

    • cgyvbunji 3 days ago ago

      > American [rail] was built on the cheap, and is not maintained correctly

      edit: I'm not sure anymore; I know most of the network is well maintained, but there could be large sections that are not, I'm not up to date on it.

      • defrost 3 days ago ago

        It's certainly been doing better since the previous US administration put some cash in the infrastructure jar.

        2025 Infrastructure Report Card | ASCE

          The 2025 grades range from a B in ports to a D in stormwater and transit. For the first time since 1998, no Report Card categories were rated D−. Among the 18 categories assessed, eight saw grade increases. 
        
        ~ https://infrastructurereportcard.org/

        I dare say the next report card might not be so rosy.

        Rail: B-

        ~ https://infrastructurereportcard.org/cat-item/rail-infrastru...

    • 3 days ago ago
      [deleted]
    • kylehotchkiss 3 days ago ago

      We have like 220,000 miles of railroad. We do have nice things: a working freight railroad system that helps reduce transit costs.

      • AlotOfReading 3 days ago ago

        If the freight rail system were as good as it should be, long distance trucking would be a rounding error instead of the dominant freight mode.

        • coryrc 3 days ago ago

          Long distance trucking gets heavily subsidized by all other road users. Damage is caused by the fourth power of weight, but trucking only paid 35% of maintenance while being responsible for 99% of the cost.

          https://truecostblog.com/2009/06/02/the-hidden-trucking-indu...

        • anonymars 3 days ago ago

          Trucks and trains serve different purposes. My understanding is the US has a higher percentage than most of freight carried by rail. Indeed at the expense of its passenger rail

          • TylerE 3 days ago ago

            Airlines killed passenger rail, not freight. Prior to it all being rolled into Amtrak virtually every railroad was losing money on passenger service.

            • reaperducer 3 days ago ago

              The Post Office shifting mail transport from trains to planes is what changed the economics.

              The passenger trains also carried mail, which helped make them profitable. Then the mail, and the money, moved to passenger planes.

              • Scoundreller 3 days ago ago

                Canada is moving away from moving regular mail by air to cut costs.

                Dunno if it will move by train or truck.

                Probably too late to add much volume on the ground.

  • simon04 3 days ago ago

    Italy has been doing this for decades.[citation needed]

  • kazinator 3 days ago ago

    > Union Pacific Is Tackling Rail Heat to Keep America’s Freight on Track

    Someone talked to an LLM which convinced them they had a brilliant idea.

    Just a guess ...

  • dnemmers 4 days ago ago

    Reducing derailment by decreasing track movement by painting the does of the track white, to reflect heat absorbed from the sun.

  • vivzkestrel 3 days ago ago

    - maybe consider electrifying the entire freight network of the USA like some of the other countries have done (mind you very large countries)

    - then you might not have to worry increasing heat levels that much

    • gblargg 3 days ago ago

      Why would electrification prevent track from warping due to heat from the sun?

      • vivzkestrel 3 days ago ago

        cuts down carbon footpriunt which in the long run ll help cut down temperatures

        • Paradigm2020 3 days ago ago

          There's a lot more low hanging fruit with higher payoff than optimizing all rail in the USA.

          Also, a guess, but I think you might benefit from checking out the actual size of countries vs the Mercator projection size of countries.

        • heisenbit 3 days ago ago

          If we are in the long run stabilising that would be already a win. Until the temperatures go down it will be a long, long, long time if ever. So temperatures will go up and we have to adjust. The scale of required adjustments is not understood yet and the increasing number of surprising needs to adjust is scary.

        • gblargg 3 days ago ago

          If we get to a point where direct sunshine all afternoon isn't hot, we're going to be in a big block of ice.

        • throw1234567891 3 days ago ago

          there’s a genius here, the crème de la crème of today’s thinkers

  • acyou 3 days ago ago

    Paint everything white! Why stop at rails?

    Mostly because it doesn't stay white and looks bad. But it doesn't stop people from painting their siding white, for example.

    Why paint the sides of the rails? Well you can paint the tops, but it tends to gum up the wheels and get worn off.

    You want a paint with high reflectivity and high emissivity. Just be sure you aren't using infrared light temp measurement as to measure and make claims about differences in temperature, emissivity is something to watch out for when measuring temperature in that way.

    20 degrees is surprising, I sure wish my car was white in the summer.

    I wonder if you have okay effects with white rails in the winter?

    • kazinator 3 days ago ago

      The top of the rail is already white!!!

      It's just polished, so that it is reflective.

      If you sanded it with your 180 grit paper, you would get the scattering which appears white.

    • phil21 3 days ago ago

      > Why paint the sides of the rails? Well you can paint the tops, but it tends to gum up the wheels and get worn off.

      Tops of rails are already pretty shiny for any mainline track seeing a couple dozen trains a day. I'd bet they are more reflective than white paint could be. And the paint would be gone after the first train passes through anyways.

      They rust pretty quick, but with regular use it doesn't build up much since it's constantly being worn off from the wheel friction.

      • mjevans 3 days ago ago

        Thank you, I was wondering why the need for paint rather than side polishing and the added knowledge that this blend of Steel rusts would ruin that for the non-contact surfaces.

        Painting it cheeper than polishing. But I wanted to know the reason they needed to / that made it so.

      • 3 days ago ago
        [deleted]
    • MrDrMcCoy 3 days ago ago

      I recall a test initiative was done some time ago for painting (or mixing in, I forget) roads teal. It improved the heat island where it was placed, and wasn't too bright for motorists. I wonder why that never went anywhere...

  • kelseyfrog 3 days ago ago

    You can literally buy derailers[1]. People will find away around this, making white paint useless. Engineers need to engineer.

    1. https://www.aldonco.com/product-category/derails/

    • hhh 3 days ago ago

      this is tackling regular natural derailment incidents not terrorism

    • trollbridge 3 days ago ago

      Derailers are common and are placed where people are working on tracks so a runaway car will go off the tracks instead of hitting the workers.

    • advisedwang 3 days ago ago

      OK, but a heatwave isn't going to buy a derailer

    • defrost 3 days ago ago

         Do NOT use where speeds exceed 5 m.p.h.
      
      Not sure what you're thinking of, but these widgets you linked won't solve the problem of long rail sections heating up in the sun, buckling, and derailing freight trains travelling at normal speeds.
    • StilesCrisis 3 days ago ago

      Why worry about memory safety? Users can literally "kill -9" anyway.