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Painting the sides of railroad rails white to reduce derailment (up.com)
atourgates 24 hours 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 23 hours 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 21 hours 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 18 hours 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 18 hours 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 11 hours ago [-]
You can even see the asphalt "waves" pushed by the buses stopping here over and over again
cwillu 19 hours 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 22 hours 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 21 hours 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 20 hours ago [-]
Yep, I use a soda can and have never had any issues.
esseph 19 hours ago [-]
My bicycle did this as kid in the summer
15 hours ago [-]
Dah00n 12 hours 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.
throw1234567891 7 hours 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.
olyjohn 5 hours 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.
Wowfunhappy 2 hours 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.

thaumasiotes 18 hours 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.

albumen 14 hours ago [-]
Or just have the cyclists use fatter tyres.
dgoldstein0 13 hours 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 11 hours ago [-]
You can buy faster bikes than what is allowed at the Tour, so the only concern would be making records incomparable.
Dah00n 12 hours ago [-]
And yet fatter tyres are faster than the slimmer ones they used to run. No-one run slim tyres these days.
webnrrd2k 50 minutes 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 12 hours ago [-]
Fatter wheel is better than a dnf right?
throw1234567891 7 hours ago [-]
Not really. If you finish second, you are the first to lose.
amiga386 22 hours 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 22 hours ago [-]
Maintenance is expensive, profits are now!
euroderf 6 hours ago [-]
A new mantra for Wall Street.
edoceo 19 hours ago [-]
I hate that you are both correct.
kmeisthax 18 hours 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 17 hours ago [-]
This of course beeing the effect of seemlessly welded together rail with nowhere to go..
jimnotgym 13 hours ago [-]
Indeed. Didn't they used to have expansion gaps?
cgyvbunji 12 hours 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.
elric 13 hours 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 9 hours 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 21 hours 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?

toast0 39 minutes 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.

adrianmonk 21 hours 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.

earth-tattoo 21 hours ago [-]
You are misreading. Basically the white paint is "fighting the sun's heat".
foxglacier 15 hours 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 12 hours 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
conorcleary 12 hours ago [-]
Fighting like a verb I think
DaiPlusPlus 17 hours 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 7 hours ago [-]
The question applies more broadly than Union Pacific. Why hasn't this been an industry standard for 100 years?
londons_explore 12 hours 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 5 hours ago [-]
Or they have a heavy rust converter (phosphoric acid?) built into it. Similar to a self-etching primer.
gattilorenz 6 hours 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 6 hours 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?

kylehotchkiss 23 hours ago [-]
I love a simple solution to billion dollar problems
conorcleary 12 hours 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.

Havoc 10 hours ago [-]
20 degree drop. That’s crazy
dupontcyborg 20 hours ago [-]
this isn’t the point of the story, but is that paint truck driving on the railroad tracks?
LarsAlereon 19 hours 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 19 hours 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.
cucumber3732842 12 hours ago [-]
They just use custom rims.
simon04 8 hours ago [-]
Italy has been doing this for decades.[citation needed]
jeffrallen 23 hours 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 23 hours 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 11 hours ago [-]
Or paint that turns black at low temp and white at higher temp?
cgyvbunji 12 hours 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 11 hours 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...

12 hours ago [-]
kylehotchkiss 23 hours 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 22 hours 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 14 hours 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 22 hours 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 21 hours 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 12 hours 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 5 hours 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.

kelseyfrog 20 hours 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 18 hours ago [-]
this is tackling regular natural derailment incidents not terrorism
trollbridge 18 hours 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 20 hours ago [-]
OK, but a heatwave isn't going to buy a derailer
defrost 19 hours 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 9 hours ago [-]
Why worry about memory safety? Users can literally "kill -9" anyway.
dnemmers 1 days ago [-]
Reducing derailment by decreasing track movement by painting the does of the track white, to reflect heat absorbed from the sun.
kazinator 20 hours 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 ...

vivzkestrel 19 hours 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 16 hours ago [-]
Why would electrification prevent track from warping due to heat from the sun?
vivzkestrel 16 hours ago [-]
cuts down carbon footpriunt which in the long run ll help cut down temperatures
Paradigm2020 14 hours 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 12 hours 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 12 hours 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 6 hours ago [-]
there’s a genius here, the crème de la crème of today’s thinkers
acyou 21 hours 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?

MrDrMcCoy 2 hours 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...
kazinator 20 hours 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 20 hours 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.

15 hours ago [-]
mjevans 19 hours 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.

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