Great column. I’ve often wondered about this.
I agree. Very interesting, but I found what I assume to be an error. At one point in the column Cecil states:
Would I be right to assume that The Master was somehow displeased with the zero?
You might think that, but see here:
On page 8, for Region I it gives 26 ft/s for the steel sphere, which is:
26 ft/s60 s/min60min/hour/5280 ft/mile = 17.7 mile/hour
I’m not sure what the mass of a one-inch steel sphere is at the moment, but certainly the kinetic energy of the sphere at 17 MPH would be insignifcant compared to a 15 foot length of 6-inch inch pipe and a 4000 pound car traveling at 92 MPH. Heck, I would bet that a baseball thrown by a major league pitcher would deliver more KE than the sphere.
What’s the point of that standard? It seems utterly useless.
I’ve worked at several different nuclear plants. I’m at work and can’t dig up a cite right now, but IIRC, not only do reactor buildings have to have thick concrete walls, but also a shield wall around the reactor itself. I forget what they call it; blast shield, projectile shield or something. Also IIRC I believe the design called for it being able to withstand a small plane crash.
“F5”
I do not think that word means what you think it means.
You may find the following video relevant to the airplane crash question. It’s youtube of slow-motion footage of an F-4 on a rocket sled at Sandia Labs, impacting a several foot thick concrete wall. As I remember, this was to help research whether a containment dome structure could survive a high-speed impact from a airplane. I remember reading the results were total destruction of the plane, and the wall moving back a few inches but not being penetrated.
I have a difficult time imagining a nuclear power plant being harmed by a tornado to the extent of releasing radioactive material. My WAG is that the worst that would happen is the civilian equivalent of a SCRAM and mangling of whatever electrical gear was outside the containment structure.
As far as spent casks go, I’m not sure whether a tornado could do more than roll them a short distance on their pads. Yet another Youtube video shows some of the, frankly Acme-esque, tests Sandia devised to try and crack one of them open. Not sure even an F-5 tornado can top that sort of force. Cooling spend fuel structures in ponds might be a different story.
(All these Sandia videos remind me of Santo Rugger. Hope he’s doing better.)
Actually the NRC objection to the AP1000 design is that it uses an innovative modular design for the containment that the NRC doesn’t understand and Westinghouse hasn’t provided enough documentation to prove the design is adequate.
The AP1000 uses a passive design where the emergency cooling water is in a tank on top of the containment building, so it can released without using pumps in a emergency. The NRC isn’t convinced that the containment building is strong enough to support the weight of the tank under all design basis events. Design basis event is nuke speak for when the fecal matter hits the fan.
Westinghouse, OTOH, claims that even if a Jumbo jet crashes into the building, it won’t breach the containment. That’s an optional design basis event.
A good question. It appears to be similar to hail-resistance standards currently applied to buildings and other structures, but I do not know for certain.
But what if the storm was… perfect?!
Well, it’s only a research reactor (for making isotopes and trying out new theories), but the nuclear reactor on the Kansas State University campus got hit by a tornado two years ago. Facade of the building was pretty damaged, but the reactor itself was fine. (The physics building where I work next door wasn’t so lucky, part of the roof was gone and they had to close down for a week to check for more serious damage.)
—Dave
As part of a late '70s HS Chem class field trip to Dresden Nuclear outside of Morris, IL, we were supposed to come up with an intelligent question to ask our tour guide. Mine was on this very subject (“What would happen to the facility if it suffered a direct tornado hit?”)
The tour guide’s response of, “That will never happen; next question?” didn’t exactly instill confidence.
My Dad ran the F-4 test. He ran the Sandia reactor safety division for a long time. I had pics of that crash a little while after he ran it*. The test was run to get some base line numbers on the impact. The deepest dent in the wall, IIRC, was about 4 inches. The wall was 12 feet thick.
I asked him about this and his answer was that a tornado ain’t gonna hurt the containment dome. Not a chance. In the video that Gray linked to the F-4 was going about 480 MPH.
Slee
- He was asked, IIRC, by a Japanese company what would happen if a plane hit a containment dome. So he tested it. He gave me a set of 8x10’s of the impact which, sadly, I don’t have anymore, about a week or so after the test. He gave me the pics stating ‘This is what I did last week’. How cool is that?
I bet your dad could beat up my dad.
Only if he had time to prepare a theorem on how to beat up your dad. He is a math geek after all.
Slee
Very interesting column which got me thinking about the Koeberg Nuclear Power Station. This is the only nuclear power station in South Africa (and possibly the entire African continent).
Koeberg was built during the 1970s / 1980s Apartheid era in South Africa’s history and therefore it had to be able to withstand possible “terrorist” attacks.
The plant is open to the public and I recall during a visit about 15 years ago that the plant (or at least the reactor building) had to be designed to survive:
(1) A direct hit from an oil tanker (It is located on the coast)
(2) A direct hit from a Boeing 737 (I think 737…memory is a little rusty).
Glad to be able top share !
What if the Boeing 737 had a treadmill assist?
D&R
The important part of a nuclear power plant, the reactor, is housed in a building called the containment. It is designed to withstand the direct impact of a 747 at landing speed, as well as internal pressures well above atmospheric. Other structures around the plant are not that robust, but don’t have to be for nuclear safety purposes.
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M"F"K, thanks for chiming in. There was already a thread on this subject, so I merged your post in with it.
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Holy crap, that video is awesome. They even used JATO rockets on the locomotive for added awesomeness. (A diesel loco like that should have no problem getting to 84 MPH on its own-- maybe their track was too short?)
I also love how they crash the cask, then immediately challenge the same cask to another incident!
Man, if only I had millions in government nuclear research funding…