In a First, America Dropped 30,000-Pound Bunker-Busters—But Iran’s Concrete May Be Unbreakable, Scientists Say
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Previously, a yield strength of 5,000 pounds per square inch (psi) was enough for concrete to be rated as “high strength,” with the best going up to 10,000 psi. The new UHPC can withstand 40,000 psi or more.
The greater strength is achieved by turning concrete into a composite material with the addition of steel or other fibers. These fibers hold the concrete together and prevent cracks from spreading throughout it, negating the brittleness. “Instead of getting a few large cracks in a concrete panel, you get lots of smaller cracks,” says Barnett. “The fibers give it more fracture energy.”
"no, these missiles only bust the bunkers we tested them on."
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I think that was kinda the idea - war production meant steel was in great demand, and this seemed like a really cheap way to make ships. I wouldn't want to try sailing one round the Caribbean, but they might have been okay in the north sea, for example. They didn't work out though, can't recall why but it's not impossible that melting may have been a factor!
The idea was to build giant floating barges in the mid North Atlantic for sub hunting escort aircraft to refuel halfway across. The escort aircraft at the time couldn’t stay with the convoys the whole way, leaving a stretch in the mid Atlantic where they were vulnerable. An ice runway would allow aircraft to cover the convoy for the entire passage, and in the North Atlantic would last months (if not longer) before melting.
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Unfortunately (?) HF is a gas.
inste-edit: I know I'm being pedantic and a reasonable concentration of hydroflouric acid is what you were talking about.
There was an article somewhere about a 1 tonne spill on chlorine triflourideThere was a "etch your VIN in your car window glass" campaign around here years back, they had a liquid solution of HF that they were wiping across printed stencils to do the glass etching. The fact that its natural state is a gas just makes it all the nastier to handle - and possibly even more effective at diffusing through the cracks to cause hydrogen embrittlement of any steel reinforcement it may come into contact with.
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They mean mixing in steel dust or nylon hair?
Hard to believe this is a recent enough thought.
Fiberglass, carbon fibers, or small steel wires. They don't need to be long, the snippets are only a few centimeters in the video I have seen.
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rest of Tokio is mostly intact
and housing becomes much more accessible too when buildings are intact but their inhabitants have much shorter lives because of radiation
Eventually, the radiation will be gone.
Hiroshima and Nagasaki are habitable now btw
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Previously, a yield strength of 5,000 pounds per square inch (psi) was enough for concrete to be rated as “high strength,” with the best going up to 10,000 psi. The new UHPC can withstand 40,000 psi or more.
The greater strength is achieved by turning concrete into a composite material with the addition of steel or other fibers. These fibers hold the concrete together and prevent cracks from spreading throughout it, negating the brittleness. “Instead of getting a few large cracks in a concrete panel, you get lots of smaller cracks,” says Barnett. “The fibers give it more fracture energy.”
If it's reinforced steel concrete, it would be much harder to bunker bust.
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I suspect the world would be safer if everyone just let Trump think he won.
That's impossible. "Make America Great Again" is a slogan that he can only abuse as long as there are problems. If he wants to stay in power it's in his best interest to create problems. It's what fascists dictators have been doing since forever. Even if there are no problems they will point towards something and make you think it is a problem, so they can market themselves as the solution. If he would "win" he would lose his power, which is obviously the opposite of what somebody like Trump wants.
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They mean mixing in steel dust or nylon hair?
Hard to believe this is a recent enough thought.
Its called FiberMesh
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I doubt it's a recent thought, knowing civil engineers, they're absolute perverts when it comes to concrete.
It has been around in some form since there has been manmade concrete.
Personally, I bought a box of chopped fibers for inclusion in a concrete project some 30 years ago - sold labeled for that specific use.
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I think that was kinda the idea - war production meant steel was in great demand, and this seemed like a really cheap way to make ships. I wouldn't want to try sailing one round the Caribbean, but they might have been okay in the north sea, for example. They didn't work out though, can't recall why but it's not impossible that melting may have been a factor!
Fuel requirements could get to astounding levels, even with ambient air and water temperatures below 0C any "hot stuff" onboard (engines, lights, radios, people) would have to be offset with some kind of refrigeration system, which requires: more fuel to be burned. I'm sure you can "stay ahead of things" in some environments, but it won't be cheap on the fuel side of things.
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I never really got why tactical and strategic nukes are so wildly different. Aren't those words more or less synonyms?
In common usage they're equivalent to small and big. In practical terms, all nukes are strategic - use of a nuke has profound global diplomatic repercussions.
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That's impossible. "Make America Great Again" is a slogan that he can only abuse as long as there are problems. If he wants to stay in power it's in his best interest to create problems. It's what fascists dictators have been doing since forever. Even if there are no problems they will point towards something and make you think it is a problem, so they can market themselves as the solution. If he would "win" he would lose his power, which is obviously the opposite of what somebody like Trump wants.
That is depressingly insightful. See also: the internal war on everyone who isn't a middle-aged white cis het man (and even some of them, too). Just negativity all around.
What really brings me down it's the certainty that even if that is guy was suddenly not there anymore, there is a whole gaggle of like folk ready to continue that same rhetoric. How do you even dig yourselves out of that?
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That is depressingly insightful. See also: the internal war on everyone who isn't a middle-aged white cis het man (and even some of them, too). Just negativity all around.
What really brings me down it's the certainty that even if that is guy was suddenly not there anymore, there is a whole gaggle of like folk ready to continue that same rhetoric. How do you even dig yourselves out of that?
That is depressingly insightful. See also: the internal war on everyone who isn’t a middle-aged white cis het man (and even some of them, too). Just negativity all around.
Yes. Separating the people is an extremely strong tool in the authoritarian handbook. It is such a strong tool that the things it accomplishes are too much to list here. There are a lot of books on the matter. I think it's even explained in some of the CIA books.
What really brings me down it’s the certainty that even if that is guy was suddenly not there anymore, there is a whole gaggle of like folk ready to continue that same rhetoric. How do you even dig yourselves out of that?
This is not completely correct. People fighting back against their oppressors sends an extremely strong message. And it even goes both way. For example, the attack on the USA Capitol of January 6th gave these Magazis a lot of power because they saw unity in their oppression.
The good thing is that there's always more good people than bad.
