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Conductive Concrete Offers Building Security
zdburke writes: "In a slightly different spin on the electromagnet-protected server room in Stephenson's Cryptonomicon, the folks at the National Research Council have developed concrete that conducts electricity, or 'percolates,' allowing it to serve as an electromagnetic shield. Current uses lean toward heated loading docks, non-freezing bridges, and grounding large-scale electrical equipment, but the counter-espionage idea is cool. The NYTimes has a brief story, and the folks at UN Omaha have some great pictures. It's not exactly new (it won a Popular Science prize in 1997) but it's still cool stuff."
Anyone remember the name of that psychologist that put dogs in a room with an electrified floor? I wonder if they'll start putting this stuff into jail cells and mental hospitals. You know, the prisoner/patient/subject mouths off they can give them a jolt. All in the name of science, of course.
So, does this mean that in the future, demolition companies could just HERF a building down instead of going inside and setting explosives?
Eve Fairbanks says I drive a hybrid!LOL
I wonder what kind of cell phone signal I would get in a conductive-concrete building? Probably next to none...
- For the complete works of Shakespeare: cat
"...but it's still cool stuff."
:)
Wouldn't "hot stuff" be more appropriate?
Is the cost per cubic foot much greater than standard concrete? If not, then I'd be interested in the implications for using it as a residential flooring substrate. Rather than going for a standard radiant heating system, would it be more efficient to employ this?
Pax Digitalia
I'm not a huge expert in the realm of physics (dammit, Jim, I'm a computer scientist!), but is this anything like a massive Faraday cage, which would prevent electromagnetic waves for entering and exiting?
:-)
I shudder to think of the day when we will work in protective buildings like these, keeping company secdrets safe from Van Eck phreakers and war drivers, but also keeping out the mellow, smooth sounds of Office Light Jazz 94.7.
Karma: Excellent Birds (mostly as a result of listening to Laurie Anderson)
Cool! Built in lightning rods, too?
Anyone remember the name of that psychologist that put dogs in a room with an electrified floor?
Pavlov. That was one of several experiments involving behaviour modification.
Eve Fairbanks says I drive a hybrid!LOL
So this stuff can conduct electricity, meaning it could generate a magnetic field, right? So you could theoretically generate a magnetic field to hold a concrete structure made from this stuff in the air. Does this mean that my goal of making a floating castle like all the bad guys in RPG video games have is finally within reach?
That unomaha site has one of the worst web designs I'ver ever seen. I guess it's not that important that scientist be designers, but readability would be a good thing to strive for. I don't need every paragraph to be a different color. Is this a side effect of too much exposure to conductive concrete?
Starsucks
to get out my multimeter, or even better, hook a big ass battery up to it and see what I can shock!
I remember when a friend was recording a radio theatre show, the studio had chicken wire on all the walls (behind accoustic foam in most places) to minimize inteferrence from outside signals. You don't want your microphone cable picking up radio signals when recording a performance. This material could be ideal for construction in applications like that where you want to block out outside signals.
How about drywall transistors and logic-gate carpets?
I wont be happy till my split-level serves pr0n.
(2,3-Benzopyrrole)
Now there is what every trucker needs for those cold winter days.
Brought to you by science.
the heating properties alone look great to me.. I live on a hill, and my sidewalk is always a nightmare in the winter.. how much do these concrete pavers the article mentions run and where can I buy them? I'm sick of using a sled to get to the bottom of my sidewalk!
ChuckyG
It kills slugs too. Who knows what good slugs do for our environment? Haha
I just sent an email alerting Vincent Flanders. I'm sure he'll love this one.
Miko O'Sullivan
Please study a little science before you post stories from similarly unclued "visionaries".
The most obvious use is heating.
But wouldn't it be cheaper and simpler to embed, say, a PVC 2-inch pipe in the concrete, and run warm water through that? Note that you can use this method with just about anything (dirt, asphalt, etc) and keep it from freezing.
If you want a method to directly heat it using electricity, run stainless steel pipe instead, and use it as a load.
I've frequently wondered why civil engineers haven't implemented either of the above techniques before. Chalked it up to "roads don't freeze enough".
Thoughts?
Don't sweat the petty things. But do pet the sweaty things.
Now even the underprivileged will be able to afford to stop the MLB from reading their minds. No more tinfoil hats!
The Soviets pioneered innovative uses of concrete way back in the '80s... though I don't think they were that interested in *counter*-espionage...
No man is an island, but Gary is a city in Indiana.
First day here, huh?
This next song is very sad. Please clap along. -- Robin Zander
Would having conducting concrete make it easier or harder to prevent electrochemical corrosion in reinforced concrete?
Intuition is telling me "yes to both", but I'm not a Civ...
If your intrested in kind of stuff New-Technologies has a good article about it. They also have a bunch of links to related sites reguarding concrete advancements.
No I'm not trolling.
Awhile ago there was talk about a government agency that ionized their concrete walls to attract airborn particles, which could then be swept away with a sponge-mop. The result was very clean air in the building (assuming the walls were cleaned frequently).
It sempt like a good idea but I haven't heard anything else about it for quite awhile. Perhaps someday this tech will be common in homes, as people are becoming more conscious of home and workplace health in our increasingly estrogenic society.
Radient heating. If they can use this to heat loading docks et. al. then how about my bathroom floor? Those stone tiles are so dang cold on the tootsies...
Do a google search before posting.
You can now go beyond wearing the tinfoil cap and build bunkers out of this (you want to be physically secure, too, don't you?) where you can run about naked telepathically communing with the trusted few you allow to enter, as well as your 26 cats of course.
Of course, remember, just because you're paranoid doesn't mean they aren't out to get you...
Sure I'm paranoid, but am I paranoid enough?
How much juice will a cubic meter of the stuff use per degree celsius? Would widespread use of this concrete create a major spike in energy consumption or would it be more efficient than current heating methods. I, for one, am sick of seeing power being wasted and never ending power generator construction.
It is by the juice of the coffee bean that thoughts acquire speed, the teeth acquire stains. The stains become a warning
.....Could give new meaning to the words Information Superhighway
:-)
Wow. Could you image transparant conducting concrete. I think it could lead to some very interesting lighting effects.
Lemme 'splain something to ya. When you have a process removing heat you've got to add heat at the same rate to keep the temperature the same. It doesn't matter if the water is already frozen or not if the temperature is below 0C the energy requirements are the same (modulo a little runoff, but in that case it must be raining so it isn't 0C anyway, not to mention 2 cm is an understatement).
Actually, the concrete, if it is like normal concrete, would probably explode instead of melting...the little air pockets inside it expand until they break the structure. It's neat. Hold a blowtorch to some concrete sometime---it crackles!
Don't worry. You'll just connect to officelightjazz.com and listen to the streaming radio. Heck, some people do this already. :-)
They laughed at Einstein. They laughed at the Wright Brothers. But they also laughed at Bozo the Clown. -- C. Sagan
It sounds like the concrete still has a pretty high resistance, so I wouldn't count on a reasonable thickness forming a good Faraday cage. With the conductive stuff costing At 2 or 3 times as much, you could likely get a better cage for less by just hanging metal mesh inside the forms and pouring regular concrete. (The mesh is part of your reinforcement, too.)
And the suggested use of electrically heated payment leaves me wondering where they plan to get free electricity.
But there is one good application for this. Electronics manufacturers need to control static throughout their facilities. Fixed objects are grounded by hooking up wires, but people walk around, circuit boards and parts are carried around on carts, etc., and the only way to ground these while in motion is through the floor. So we paid plenty for conductive tile, and some sort of conductive underlay. If we could have put a conductive layer in the concrete slab itself, it would have saved a bunch (even at 3x the price of regular concrete), and it would be more reliable and lower maintenance.
now maybe those alien abductions will stop and I can get on with my life. :)
Do you not have anything better to do with your time than bitch and moan about an informative article because it doesn't use your lexis?
Kindly grab both of your ears tightly, one in each hand, and pull firmly until your head is extricated from your ass.
Keeping something from freezing requires exactly the same amount of energy as melting it. Exactly. This is obvious to anyone who has studied science or used an ice cube.p. The waste produce is always heat. But it isn't always released near any ice. What about the sides and bottom of this road? What about patches of ice? What about transmission issues?
For people who talk all geeky, this site sure is scientifically illiterate. The heat of fusion (esp of water) vastly overpowers the specific heat of even something as large as a bridge. Wind could be a problem, though.
they already have heated parts of road in midtown here.(finland). it's supposedly just about the same price as it would be to use conventional salt and/or machines to keep the ice/snow out. AFAIK they turn it off at -15C or so.
world was created 5 seconds before this post as it is.
Again, the URL is: http://www.majcher.com/nytview.html
It's a simple HTML/javascripty thing to automatically generate a random NYTimes login every time you want to view a story. Just cut and paste the nytimes.com url you want to view, and hit the button.
If you could, please try to save the page locally and use it from your server or desktop, to keep the traffic to my server reasonable. Distribute at will.
Would be great for movie theaters and the like...
-- Adam
SpinalTap could have really used this technology when Niles was wielding his wireless guitar...
"These go to eleven."
"And like that
I thought a big use for these were going to be for heated runways - so you don't have to worry about de-icing them anymore. (I just hope they don't heat them too much and then you have a bunch of lizards just hanging out on the runway warming themselves.)
Where the wind blows, the tumbleweed goes.
This conductive concrete has some interesting properties. The number one use that leaps to mind is EMI protection.
:) (I don't think anyone has proven that non-ionizing radiation causes cancer yet, so no worries...)
But for heating? Forget it! Two replies to this article mentioned something about how much energy it would require to melt ice. Now add the energy required to heat up the concrete. And know, that while electricity works quickly, it is just about the most expensive way to heat your home/whatever.
You might consider also, that while an abode of conductive material might be a great way to absorb stray radio signals coming your way, what are is your dwelling going to be emitting if you are hooking up AC voltage to it? If a micro-watt cell phone freaks you out, consider thousands of watts pumping through your house
Radiant heating systems are the way to imbed a heat source in concrete. The technology is gaining in popularity all the time, as it deserves.
Read more about it for yourself at: http://www.radiantcompany.com/ They are for profit, but the prices seem reasonable. They advocate do-it-yourself and lots of good info on the website.
It would be great to hear from an HVAC engineer on this, but I don't think they will tell you much different.
Bollux (a BSME)
geesh, slogging my way through this enormous book - i haven't read about any 'electromagnet protected server room' yet - thanks for giving it away.
www.pixelectric.com
In the post for this article, the author writes like an enthused teenager, not like a professional.
plz point me to a certain 'rule' which requires people posting articles to use 'professional' terms
If large structures are made with conductive concrete, it could create a broad spectrum RF nightmare in cities.
Today, large buildings reflect radio signals, creating interference for many signals in the shorter wavelength (6m to 30cm) bands. Imagine how much worse this would be if the buildings them selves had strong electromagnetic fields, or worse yet, emitted AC fields?
Also, these structures will convert radio signals and other EMF into electric current. Theoretically, it is possible that such current could be in the tens of milliamps or even higher, making for passive RF radiators.
I know we already use a lot of steel in buildings, but this is usually grounded and steel is a really poor conductor compared to something like copper or silver. I'm assuming this conductive concrete has much better electric conductivity than steel.
Vortran out
Knowledge is like ignorance.. too much can be just as bad as not enough.
Something I discovered with a neon transformer is that most things are conductive to some degree if you apply enough voltage :) concrete included.
JET Program: see Japan, meet intere
... when we start applying the Seebeck Effect. In fact, we would want the largest possible temperature differential possible, since this would maximize our power gains. Bridges and large buildings would be a fun way to generate power.
So why melt the ice when we can use the temperature difference between an ice-forming-bridge and the temperature stable ground (or even the body of water the bridge crosses) to generate power for pr0n serving apartment complexes?
And we can drive our new electric vehicles slot car style, by drawing power from the road itself.
For anyone caring to post a reply to PhysicsGenius' post, I suggest you read through some of his previous posts. http://slashdot.org/~PhysicsGenius/ Well trolled. :)
You have enemies? Good. That means you've stood up for something, sometime in your life. --Winston Churchill
De gustibus non est disputandem.
The fact that you don't fancy somebody's writing style style doesn't make it crap; it just means you don't like it. Lighten up a little. Sheesh.
I have read this, and i understand most of these conceps, but what bugs me is what will you do when the cincrete slab starts cracking? Then we'll end up with uneven disrtibution, crews will have to be called in to make repairs (if possible, nobody mentioned the method of repair) and finally let's not forget the bridges (the hottest topic of 'em all) the article (or someone) said that the conductive concrete will be "sandwiched" between the layers of "standard" concrete, which means that if any cracks are to occur crews will have to be called in to repair anyway (as they would with PVC pipes or stainless tubes) so i wonder if the whole thing will still work in about 15 years down the road... :)
Live for the present, learn from the past, and dream of the future!
*throws snowshovel out window*
Use my userscript to add story images to Slashdot. There's no going back.
Again, I am proved right. Where can I get my copy of Finux?
TANSTAAFI: There Ain't No Such Thing As A Free iPod.
Oohhh.. I just went and looked at the rest of his posts. Here are some of the best parts:
"Yes, the CPU produces heat but keep in mind that a server room is a closed environment--no energy (e.g. thermal energy) is actually created. The heat produced is given off by the entropy reversal of information being created. When that information is destroyed, in practical terms just deleting a file, some of that heat is sucked back up and it cools the room back down."
"I am a prime physical specimen. "
"I love science. I love big science. But science is more than pretty pictures. It is a process of creating, testing and destroying hypotheses to push our knowledge to the edge of the envelope. The Hubble telescope does none of these things. Of course, neither does an electron microscope or a hammer--because they are merely tools. But when wielded by a trained, creative and insightful scientist they can help produce startling new theories that make our life better. But the Hubble telescope isn't in the hands of trained, creative and insightful scientists. It is in the hands of bureaucrats and politicians who dole out a minute here and a minute there on whatever pet projects they happen to favor. When Scientist A creates a theory based on an observation made with Hubble, these chairwarmers refuse to let Scientist B use the 'scope to attempt demolish that theory for fear it will make Hubble look bad. We obviously can't afford to make enough for everyone, so the only solution is to let no one have it. Decommission the Hubble! "
Here he gives dangerous advice:
"Some may say that "putting a magnet next to a HD is a bad idea" but think about the magnetic fields that already exist in the case from the power supply, nearby speakers/fans and even interference from the magnetic charge already on the disk. Putting a magnet, even one strong enough to pull a metal pin like these, near your HD presents no danger whatsoever. "
"make sure you insulate your T1 connection well to keep this heat gain to a mimimum."
No comment at this time
The bridge-deicing idea isn't unreasonable. From their numbers, for $500 per storm, you could de-ice a bridge 200' long and 4 lanes wide. That compares favorably with sending out snowplows, salt trucks, and such.
Obviously the usage will be limited to high security buildings, but hey, if you want to do that, you can just put metal panels in or on the walls.
By the same token, don't you have anything better to do than bitch and moan and people who demand better quality?
When you consider that they expect that "better quality" to come about by having the government forcefully take it from others and give it them for no better reason than they want it, then I indeed reserve the balance of my time for said purpose of bitching and moaning.
Typical american conservative.... You may now grow up, please
Typical commie euro-trash....you may actually try working for a living now.