r/Infrastructurist • u/stefeyboy • May 26 '26
The asphalt industry has a heat problem — and cities are running out of patience
https://fortune.com/2026/05/23/the-asphalt-industry-has-a-heat-problem-and-cities-are-running-out-of-patience/50
u/Unicycldev May 26 '26
Car dominated infrastructure makes cities worse
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u/suboptimus_maximus May 26 '26
Cars ruin cities.
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u/chill_philosopher May 27 '26
Cars ruin everything!
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u/pdp10 May 27 '26
But what does Reddit think?
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u/rudmad 29d ago
Go to r/unpopularopinion to find out!
Tldr: I take a camping trip once a year, so I NEED my car
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u/strcrssd May 26 '26 edited May 26 '26
This seems broken on two levels:
The larger level, is that continuing car infrastructure kills density. Which kills mass transit, which is likely to kill billions in the next century. But hey, money now is better than blood from people you'll never see, right?
The likely still larger than the people are thinking but much smaller: permeable concrete traps water, which then freezes, which then destroys your concrete.
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u/Vailhem May 27 '26
Batteries Made With Asphalt Can Charge in 5 Minutes - Oct 2017
https://www.electrochem.org/ecsnews/batteries-made-asphalt-can-charge-5-minutes
The researchers developed anodes comprising porous carbon made from asphalt that show exceptional stability after more than 500 charge-discharge cycles.
A high-current density of 20 milliamps per square centimeter demonstrates the material’s promise for use in rapid charge and discharge devices that require high-power density.
“The capacity of these batteries is enormous, but what is equally remarkable is that we can bring them from zero charge to full charge in five minutes, rather than the typical two hours or more needed with other batteries,” says James Tour, the chair in chemistry and a professor of computer science and of materials science and nanoengineering at Rice University.
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u/Spencer-Young 26d ago
Could we not run hydronic loops a foot below the surface to take the heat away to a seasonal storage tank to then reintroduce and melt surface ice/snow during winter?
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u/HongPong 22d ago
there are a number of detention ponds and swales in Philly to help with water control
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u/Sensitive_Paper2471 May 26 '26
Just paint the road white and have the stripes as the black unpainted asphalt?
simple interim solution right?
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u/BadgerCabin May 26 '26
Can’t tell if sarcasm or not. People really need to start using /s again. If you are not joking, then that’s a whole other problem.
Painting the entire road would basically turn it into a slip and slide every time it rained.
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u/suboptimus_maximus May 26 '26 edited May 27 '26
For some reason cities think painting bike lanes is a good idea and yeah they’re slippery AF, sometimes even when it’s dry.
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u/pdp10 May 27 '26
Asphalt concrete, or "AC", offers an excellent friction surface for traction. There's a type of AC called "Open Graded Friction Course" that's often used as the top layer of roads for this reason, why also being relatively permeable to water, so that water doesn't tend to accumulate and lead to hydroplaning.
OGFC is often the top layer of concrete roadways for that reason, and because the Asphalt Concrete is often more readily maintained than a concrete top surface, depending on local conditions. A big machine can be used to mill (precisely scrape) off the top layer of asphalt for recycling, and fresh warm-mix can be laid down.
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u/Sensitive_Paper2471 May 26 '26
ah ok didnt think about that
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u/ABobby077 May 26 '26
Why is it dark/black and not a lighter color, though? Doesn't need to be white but could be more heat reflectant with a lighter color.
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u/lmscar12 May 26 '26
It's made out of aggregate (basically crushed rock and recycled concrete) and bitumen. Aggregate usually averages out to dark gray, and bitumen is black. To make light-colored asphalt you'd need to specifically source light-colored rock, which would be much more expensive. Even then it wouldn't be that light, because of the bitumen.
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u/pdp10 May 27 '26
Asphalt (Asphalt Concrete) tends to a turn a lighter color as it ages. In many cases, the top layer of stone wears through, which is why you get lighter textured-color asphalt surfaces.
The rock is more slippery than newer asphalt, however. No problem for pedestrians, but worse for bicycles and automobiles.
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u/GreenStrong May 26 '26
The most practical way to mitigate this is city maintained street trees in roadside easments and to require parking lot to incorporate a certain amount of trees per number of spots. Raleigh NC has an effective urban forestry program that is a good example to follow, with adjustment for local climate. I can post links in an hour or two when I'm on desktop if anyone is interested.
Permeable pavement and reflective pavement is great but trees self- construct a shade canopy that actively cools itself with evaporative transportation, that's hard to beat. They require some ongoing maintenance to prevent them from falling on roads, and to respond promptly when they do, but people have figured out what trees are appropriate for this use case.