Third Avenue Bridge, which connects New York’s the Bronx to Manhattan, got stuck in an open position due to the high heat on Monday.
FDNY officers arrived in boats and fired water at the structure to try and cool down the metal, which expanded after high temperatures in the city, officials say.
The incident caused major traffic delays during one of the hottest days of the year in New York but reopened on the same day.
Okay… so… Republicans… I know you’re not big on science, but the Earth is not supposed to get so hot that metal expands to the point that we can’t move a metal bridge that’s reliably moved for a very long time.
Infrastructure in NY is crap, but unrelated to this particular bridge problem.
Lol you should never follow up poor NY leadership with /s regardless of the party in power. Them not thinking they needed to include extended magazines in the SAFE Act because they thought magazines were disposable and would phase themselves out as long as they couldn’t be sold, and the entire fucking legalization of recreational marijuana shit show should be more than enough to remove the /s and that’s all without including anything that shit for brains cuomo did lol
the Earth is not supposed to
I don’t think we get to say what the earth is “supposed to” do.
For most of the earths existence it wouldn’t be possible for humans to exist. I don’t think it really gives a shit about a bridge we built.
Changing topics. Good strategy.
Not even a little bit. I fully believe humans are causing climate change. It is going to make life as we know it on this planet completely different in the very near future.
I still think the planet itself doesn’t give a shit, and claiming there is a way it is “supposed to be” is pretty narrow minded.
Is official. 2024 is using early 2000 blockbusters movie’s plots now. What a bunch of lazy screenwriters.
We had a similar issue with an older bridge here in Gothenburg, Sweden. The fix was to install water sprinklers during the summer to keep the bridge from expanding too much.
Dumb question, but why is the water cooler than the bridge? Because it was underground? Or does the evaporation help because it’s endothermic?
It’s a good question. Steel is very good at absorbing and retaining heat. Water on the other hand isn’t. Metals in general have way better thermal conductivity than water.
Exposed to the sun at the same time, a piece of metal will warm up a few times faster than the water. I believe steels can be somewhere around 8-10 times less energy required than to heat a similar mass of water.
The water could even start out slightly warmer than the bridge. Evaporative cooling would also work here since there is plenty of ventilation around the bridge. But that can slow down based upon humidity level.
Because metals have way better thermal conductivity, they aren’t good at retaining heat.
Heating equal masses of steel and water the same amount takes exactly the same energy, it just might take longer for the insulator vs. the conductor.
Both. Even the river water below the surface will be cooler than steel that’s been sitting in the sun. And putting that cool water on the bridge absorbs some of the heat and is removed in evaporation, just like sweating.
Water also needs a substantial amount of energy to evaporate, hence it will sip some heat from the environment around it when it evaporates. Combined with the good thermal conductivity of steel, the bridge cools off.
You get a similar effect when walking out of a hot shower. The hot water evaporates and cools you down.
Simplified: Energy is stored as heat in matter (the jostling of atoms and molecules) and there are many more water molecules under the bridge than there are molecules/atoms in the bridge. So both the water and the metal heat up during the day and cool down at night, but since there is much more water, the water has a much more stable temperature. In short: Larger volumes of atoms have larger heat capacities.
If the water under the bridge was stagnant and a shallow puddle, then it’s temperature would vary much more throughout the day as well, but it would still warm up less than metal or soil, since a body of water loses some of it’s heat through evaporation.
This is also why coastal climate is a thing: the huge mass of water in the ocean makes it so that coastal areas are warmer in the winter and cooler in the summer.
Ah, we’ve reached the collapsing infrastructure stage of climate change. Oh good.
At least it’s effecting people responsible for climate change and not small tribes on far out islands like has been up to this point.
They are definitely not driving between East Harlem and the South Bronx. No rich people live in either of those places and they don’t connect any expensive areas.
Hurricane Sandy was the climate issue that really affected Downtown Manhattan. It’s a big part of the reasons why wealthy people actually care about climate change.
Not a bridge expert, or really any kind of expert, really. But railroad rails are laid with a little gap to account for thermal expansion of the rail on hot days. If the expansion is more than designed for, you get buckling like this. This bridge was probably also designed to account for thermal expansion to a certain degree. It seems like more and more of our infrastructure is starting to fail, encountering heat levels it was never expected to encounter. I wonder if failures like this and worse are going to become a common headline
This bridge was probably also designed to account for thermal expansion to a certain degree. It seems like more and more of our infrastructure is starting to fail, encountering heat levels it was never expected to encounter. I wonder if failures like this and worse are going to become a common headline
Bridge engineer here (not much experience, so I wouldn’t consider myself an expert, but I have more knowledge about it than the general public).
Your suspicions are correct, bridges are designed for thermal expansion. More of our infrastructure is starting to fail, and part of that is because it’s experiencing climate it was never designed for (heat, sea level rise, more drastic storm surges, etc). I would fully expect this to be a more common headline. At least for several more years, anyway. If the federal money from the infrastructure bill the US passed a few years ago runs out or is not allocated to the right structures, then this will only get more common. I don’t expect the Trump administration to champion an extension of these funds if they do run out. It was passed under Biden, after all.
As for this bridge in particular, this is a moveable steel bridge. The fact that it’s moveable means it is particularly sensitive to expansion (as well as salinity which causes rusting). Too much expansion, and the steel will get stuck in one position. In a typical steel bridge, if the thermal expansion exceeds what it was designed for, you end up getting higher stress levels in the steel as it pushes harder against the abutments. Usually this is alright in the short term, since we design these to withstand much higher stresses than it will ever likely experience. Repeated cycles of this, however, will cause fatigue failure (think of a paperclip or metal spoon snapping after you bend it back and forth a bunch).
Anyways, there you have it. I rambled for too long about this lol.
I rambled for too long about this lol.
The fuck you did! Making the world a little less dumb, one ramble at a time, is a good thing. We don’t all need to be specialists in everything, but a brief summary like this contributes to our general knowledge and is a net positive.
According to Practical Engineering, tracks are no longer given a gap. The gap causes premature wear and excess noise. Instead, they lay the track under tension, and weld the joins between sections.
There is still a limit on how much heat they can handle before buckling, of course. I just thought that was a neat innovation.
Basically, yes, though I think they have special hydraulic pullers, too. I forget the exact name. They have to take special measures if the day is too cold.
Rail is laid at a “neutral temperature” calculated from the min and max temperatures of an area. They want the rail to not pull apart in the cold or buckle in the heat. If average temperatures go up that calculated neutral temperature goes up so rail laid at a lower neutral temperature are more likely to buckle.
