In a First, America Dropped 30,000-Pound Bunker-Busters—But Iran’s Concrete May Be Unbreakable, Scientists Say
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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?
The reality is that "tactical" and "strategic" are functionally meaningless adjectives when applied to weapons or systems.
Theoretically, "tactical" refers to how a military unit engages another military unit. It is how a commander wins a battle against an enemy unit.
"Strategic" refers to how a nation engages another nation. It is how a government wins a war.
The term "tactical nuke" referred to something that a lower level commander could have been authorized to use under his own judgment. If Soviet tanks were rolling across Europe during the cold war, commanders may have been granted the discretion to use small nuclear weapons to halt their advance.
Since the the doctrine of Mutually Assured Destruction was established, there has been no such thing as a "tactical" nuke. Any wartime use of a nuclear weapon of any kind demands an escalation to total annihilation. I used the term "tactical" ironically, to refer to a pre-"MAD" doctrine that can no longer exist.
In declaring that conventional bombs cannot penetrate this fixed bunker, it seems that someone is pushing for unconventional warfare. The reality is that this bunker is not impenetrable. It shares the same weakness as any bunker: getting into and out of it. Bomb the entrances to the bunker, and it will take months or years to tunnel back in. Whatever they are doing inside it, they won't be doing until they manage to dig it up again.
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I suspect the world would be safer if everyone just let Trump think he won.
I wonder if Hasbara accounts are pressing this narrative?
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My first thought is actually getting the corrosive substance onto enough of the concrete would be difficult
Yeah, if the concrete is 40' thick and they're only getting 10' of penetration with the explosives, then this isn't going to do much. But if it's 20' thick and they got through the first 12 with HE, the remaining 8 are going to have a lot of cracks to admit slow liquid death.
I have zero information on what the reinforcers are in the concrete, so shot in the dark is about right. Glass might be tough - unless you could deliver hydrofluoric acid effectively. Metals - we're not going to want to wait for iron to oxidize, looks like hydrogen embrittlement with HF again - so maybe that's the magic sauce. Nasty stuff, but that's what weapons manufacturers are good at handling and packaging: nasty stuff.
2000 lbs of HF poured on the surface isn't going to do much to the buried chamber, but 2000 lbs of HF delivered into the freshly stressed and heavily cracked concrete layer under all the dirt - that could be a problem for future use of the facility.
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 triflouride -
IIRC this type of thing isn't new - there was research into the possibility of making ships out of ice mixed with sawdust in WWII.
It also wasn’t and isn’t that crazy of an idea.
It’s strong AF, buoyant, and you can repair it at sea using the ocean around you.
You just need a reliable way to keep it cool.
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How is the fleet holding up?
We almost made it this time!
Oh well, let's freeze another fleet, wait for January and try again
Look up pykrete, it’s actually a really cool material
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Very much not.
Tactical means immediately useful. E.g. use against troops.
Strategical means mediately useful. E.g. use against infrastructure and production capacity. Also massively killing civilians. This is where most heinous war crimes live.immediately
mediately
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immediately
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One means directly, one means by middle man. E.g. a president is elected mediatly by electing a law giving council that then votes on who becomes president. As opposed to the people electing said president directly.
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It is like a rifle vs. a cannon.
Yes it is functionally the same, but the "bullet" is much much larger.
Not really. More like a cannon and an artillery aimed at industrial capacity.
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How is the fleet holding up?
We almost made it this time!
Oh well, let's freeze another fleet, wait for January and try again
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!
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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
deleted by creator
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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.
