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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?
In the post for this article, the author writes like an enthused teenager, not like a professional. I don't know if these clowns who post articles are actual teenagers, or people trying to write "down" to teenage level, but it's irritating. And no, it's not "slightly" interesting, this isn't a "spin" on someone else's idea, and I am not "leaning" toward an opinion. The writing simply sucks. Fix it.
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.
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?
A Concrete That Percolates, Keeping Snow and Spies at Bay
By IAN AUSTEN
S ECURITY experts looking to prevent spies from eavesdropping on computers by intercepting the electromagnetic waves they throw off don't turn to Martha Stewart for interior-design inspiration. The solutions they employ are often unattractive and well beyond even her budget. For example, one involves building a room within a room out of welded thick steel plates.
But a new concrete that can conduct electricity may make it possible to construct buildings in which the basic structure does double duty as an electromagnetic shield.
Not that the scientists who developed conductive concrete at the National Research Council of Canada were looking to play a role in the world of counterespionage.
"The initial development evolved from a discussion I had with a graduate student," said James J. Beaudoin, the lead researcher and a concrete expert at the research council's Institute for Research in Construction, based in Ottawa. "We were trying to come up with projects to address the needs of people in cold climates, such as snow and ice melting." Concrete that could conduct electricity would also create heat through resistive heating.
Of course, electrical elements and pipes carrying heated liquids have long been embedded in concrete to create ice-free garage ramps and walkways. But such installations are expensive and difficult to repair.
Mary Ann Smith
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Nor, Dr. Beaudoin acknowledges, is the idea of a concrete that can carry electricity a particularly novel one. "But most of the concepts developed in the past wouldn't be useful because you couldn't build anything with them," he said. "They didn't have structural integrity."
Early on, Dr. Beaudoin and other researchers at the research council looked into using carbon fibers similar to those that are woven into special fabrics and covered with resins to create lightweight but strong parts for aircraft and sports equipment.
Less exotic fibers have long been used in concrete for a variety of purposes, like increasing its ability to deform without shattering. The lab did eventually come up with a concrete mix that retained its strength after the addition of the carbon fibers and gained the ability to conduct electricity evenly -- a property that Dr. Beaudoin calls percolation.
But as anyone who has seen the price tag of a carbon-fiber-composite bicycle knows, carbon fibers are expensive. "You have to remember we are dealing with a construction material here," Dr. Beaudoin said.
The group found a much cheaper substitute in coke breeze. Coke is essentially coal that has been reduced mostly to carbon by high-temperature baking. Most of the time it is added to blast furnaces at steel mills. Coke breeze is the leftover material that is too small for the steel industry. With coke breeze, the lab was able to create a conductive concrete that is only two to three times more expensive than ready-mix concrete.
Finding a suitable additive proved to be only half the problem. Mark Arnott, the conductive concrete project manager, said that a far bigger issue was developing special mixing, handling and curing processes that ensure consistent electrical conductivity between different batches of the concrete. "We could give you the recipe but you would most likely not be able to produce the material," he said. (The recipe would not make light reading in any case. The manual on making and using the conductive concrete runs about 400 pages.)
Because of the complexity of creating this concrete, St. Lawrence Cement, a Swiss-owned company based in Montreal that has licensed the technology, initially plans to offer it only in precast pieces.
Except for the positive and negative leads embedded in them, St. Lawrence's conductive concrete slabs look much like those sold at The Home Depot (news/quote ). At the offices of a construction company in Oakville, Ontario, owned by St. Lawrence, the concrete company built a sidewalk and a loading ramp to test the material late last year.
The winter has been unusually mild, so the system has not been overwhelmed by snow. But Peter J. Tumidajski, the manager of new product development for St. Lawrence, said that the eight times it did snow, the self- heating ramp was never more than slushy. "You never actually get a buildup of snow," he said. "It always keeps up." A 20-by-80- foot pad at the National Research Council's far more wintry grounds in Ottawa melted the snow and ice without fail for three years.
Although a relatively high voltage is used, the actual current flowing through it is small because of the high resistance of the concrete. So it is safe to touch the concrete.
St. Lawrence is dreaming of bigger things than loading ramps, however. Dr. Tumidajski hopes that the material, encased in two layers of conventional concrete, will be laid on the decks of highway bridges. The system would have two functions. When relatively high-voltage electricity was sent through it, it would melt ice and snow. But a much lower voltage could be sent through the concrete to inhibit the electrochemical corrosion of the steel reinforcing bars that are buried in it.
Several Canadian and United States government agencies, including the United States Army Corps of Engineers, have approached the research council about using conductive concrete to trap computer signals. While a variety of technologies are used within computers and monitors to limit the amount of electromagnetic radiation they throw off, high-security facilities are generally housed within something called a Faraday cage. In effect, this involves surrounding the room with metal, ranging from aluminum or copper mesh for less-secure facilities to one-quarter-inch-thick steel plate in more high-security applications.
Whatever their proportions, all Faraday cages work on the principle that a room made of a grounded, electrical conducting material will block electromagnetic waves from escaping.
Dr. Beaudoin and Mr. Arnott said there was no doubt that the conductive concrete could block emissions. "But we don't have any hard data on how such a system will react," Mr. Arnott added. Research is now under way to come up with precise measurements of the concrete's efficiency.
There is one immediate use for conductive concrete. But it makes the prototype loading ramp -- not to mention the counterespionage applications -- seem positively glamorous. In rocky areas, it is often difficult to ground radio towers so that energy will dissipate when lightning strikes. One solution, Mr. Arnott said, is "to just pour a trough of conductive concrete at the base."
Mechanical: builds weapons
Civ: builds targets
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
I like the idea of Chocobo powered airships (like in FF10) ;-)
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. :)
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.
Figures I don't even know what the guy's are working on downstairs. I work at the IRC as a coop student. Geez they have some strange projects here.
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
this renders my cool van-eck equipment i've been using to monitor nearby governments obsolete. well thank you very much.
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
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.
http://www.nrc.ca/
get it right next time you open your yap and post stupid crap
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.
From user's profile:
I am never moderated down!