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Painting the sides of railroad rails white to reduce derailment

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Re: Painting the sides of railroad rails white to reduce derailment

#71

Post by brookst »

anonymars wrote: post #8
jeffrallen wrote: post #4

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.

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?

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

Re: Painting the sides of railroad rails white to reduce derailment

#72

Post by toasty228 »

superb_dev wrote: post #37
jordanb wrote: post #20

Earlier quoted context omitted.

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.

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

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

Re: Painting the sides of railroad rails white to reduce derailment

#74

Post by GuB-42 »

elric wrote: post #52

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.

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.

Re: Painting the sides of railroad rails white to reduce derailment

#75

Post by StilesCrisis »

kelseyfrog wrote: post #26

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/

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

Re: Painting the sides of railroad rails white to reduce derailment

#77

Post by mark-r »

DaiPlusPlus wrote: post #42

> “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…

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

Re: Painting the sides of railroad rails white to reduce derailment

#78

Post by throw1234567891 »

Dah00n wrote: post #57
atourgates wrote: post #3

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…

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.

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.

Re: Painting the sides of railroad rails white to reduce derailment

#79

Post by throw1234567891 »

baq wrote: post #58
dgoldstein0 wrote: post #53

Earlier quoted context omitted.

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.

Fatter wheel is better than a dnf right?

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

Re: Painting the sides of railroad rails white to reduce derailment

#80

Post by throw1234567891 »

vivzkestrel wrote: post #45
gblargg wrote: post #44

Earlier quoted context omitted.

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

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

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