Concrete Casts New Light in Dull Rooms

opticsorg writes "Stuck for decorating ideas? Then the light-transmitting concrete that is set to hit the market this year is what you could be looking for! The days of dull, grey concrete could be about to end. A Hungarian architect has combined the world's most popular building material with optical fiber from Schott to create a new type of concrete that transmits light. A wall made of 'LitraCon' allegedly has the strength of traditional concrete but thanks to an embedded array of glass fibers can display a view of the outside world, such as the silhouette of a tree, for example."

Comments

And the reverse?

[bolix]

I don't see mention of being able to see internal objects? If the lightsource inside is stronger (nighttime), you may get the shadow puppet effect all around your house!

What about paint? You know anyone that wants gray walls in their house?

Re:And the reverse?

[p4ul13]

You're right. It is almost certain that the outside world should be able to see your "shadow puppet" at night.

As for the color of the wall, there was a picture on the site that showed a brown wall, so I guess the stuff could be dyed when it is manufactured, but I think repainting your room would be out of the question..

Re:And the reverse?

[Danse]

Yeah.. I'm guessing that this stuff won't be used for homes anytime soon. It's kind of the worst of both worlds. Who wants to hang curtains over a concrete wall? Hell, who wants to have concrete walls in their home anyway?

Re:And the reverse?

[russellh]

You're right. It is almost certain that the outside world should be able to see your "shadow puppet" at night.

Well it wouldn't be used for a house here on the US east coast. Not a lot of people live in bare concrete houses - if only because it's too cold.

Re:And the reverse?

[p4ul13]

Maybe not here in the North east (NY), but further south. Your post brings to mind another question. What happens if you get this stuff wet regularly? Will mildew completely ruin it? What about the anti-mildew treatments used on traditional concrete?

If nothing else, I'm sure we can all agree that it would be cool to make a wall of this stuff and pretend you were Superman using Xray vision.

Re:And the reverse?

[jaredcat]

You're right! Being able to see internal objects is a big no-no.

What's next? putting big glass panes in the wall? Oh wait a second...

Seriously though, there are a lot of building applications for opaque wall material. From the pictures on this website it looks like you wouldn't be able to see any more detail than you can see through those thick distorted glass bricks used in place of windows in many a public bathroom.

What is really amazing about this stuff is that it can be load bearing. Now when you want to build a huge transparent wall for cheap, you don't have to use as much glass. Or if you still want to use glass as much glass as possible, now you can have semi-transparent supports around the glass insted of just plain old concrete and dry wall.

Re:And the reverse?

[sckeener]

Might be good for parking garages.

Will the mugger behind pillar #1 please step out....

I can think of several uses (mostly involving outside projects.)

You're right though about internal objects. Unless it is an art house, I doubt anyone would do their bedroom with this stuff. I can just image the shadow play of the beast with 2 backs.

Of course, back in the 90s there was a all glass house in Brazil (I think) as art. A woman agreed to stay in the house for a few months. Every morning there would be a large group of villagers outside the house waiting for her to wake up.

Re:And the reverse?

[Mad Bad Rabbit]

You're right. It is almost certain that the outside world should be able to see your "shadow puppet" at night.

Instead of having the fibers run straight through the block, maybe they could twist or braid them; so that light could still seep through but would form random shadow blobs instead of clear silhouettes.

Re:And the reverse?

[dbirchall]

Astoundingly, "shadowpuppetporn.com" is still available.

I wonder if I can work out a way to charge admission to my front yard...

Since shadowing requires the object casting the shadow to be between the light source and the viewer, this might be an interesting material for (cast, pre-stressed) roof panels. It'd let light in during the day, and at night, any lights inside, probably being near the ceiling anyway, would give the roof a glow.

Re:And the reverse?

[Anonymous Coward]

Many a couple camping has been caught out by leaving the light on in the tent. A friend of mine took her family camping and a group of lesbians with tents turned up and did just that. This was in the New Forest, in England. Highly embarrasing for all involved.

Re:And the reverse?

[beat.bolli]

Yeah, and all astronoms will hate you for this idea...

Re:And the reverse?

[dbirchall]

very good point. Since where I live is visible from here on the rare clear night, we've got streetlights with shades to keep the light from going "up" too much and all that... so yeah, that could be a slight problem.

I'm not sure how bright the glow would be, of course...

Chernobyl

[AtariAmarok]

Then the light-transmitting concrete that is set to hit the market this year

I see some huckster has found a clever way to get rid of all that Chernobyl rubble and building material.

Cool!

[smoondog]

This is pretty f'ing cool.... This is obviously going to be interesting for art projects and houses. I bet it is expensive, however, and we won't see any skyscrapers using this stuff anytime soon. (Can it be set like traditional concrete or do you buy blocks?)

-Sean

Re:Cool!

[Danse]

rtfa... you can only buy it in pre-fab blocks right now.

Re:Cool!

[Danse]

Or will be able to buy it rather, once they start selling anyway.

Re:Cool!

[p4ul13]

I didn't find mention of it on the site, so I'm wondering if they have a special approach in mind for cementing the blocks together. When you cement them together to form a wall, you'd end up with a brick pattern obscuring the image that is showing through.

That could either detract from or enhance the "coolness" factor depending on what look you were going for I suppose.

Re:Cool!

[jaredcat]

From the pictures on the site, I imagine that they are just going to make a full piece of cement to your size specifications insted of you buying a whole bunch of smaller blocks and cementing them.

Re:Cool!

[Bazzargh]

From the pictures on the site, I imagine that they are just going to make a full piece of cement to your size specifications insted of you buying a whole bunch of smaller blocks and cementing them.

No, this picture clearly shows bricks. However generally cement isn't going to be a problem for this material. You can see that he's running fibres from one site of the concrete to the other. The light you see on one side appears in the position it fell on the other side, (look at the two shadows of the woman's right arm - the one cast outside the block is lower than the one cast through the block).

This being the case,you can create room for a channel of cement between blocks by bending the fibres, while having the blocks appear to be flush on the outside. ie:

|upper______block|
|/////CEMENT\/<--- fibre bends round channel
|___/________\___|
|lower//////block|
| ////////////////|

Re:Cool!

[Anonymous Coward]

>> and we won't see any skyscrapers using this stuff anytime soon.

I dunno, at least you'd be able to see the incoming planes.

One ticket to hell please... uh, one way will be fine thanks.

Re:Cool!

[p4ul13]

That does sound like a possible way around it (though your cement would have to be precisely placed in the center of a block and would be tough to get passed through an inspection. Another problem is that if you bent the lower fibers up in order to hide the cement space, you'd have to make up for that bend somewhere, so the top of the brick might put you back in the same situation.

Excelent use of an ascii schematic BTW.

And then come the disclaimers about the uses

[RCO]

Do not use around public restrooms, unless you want a truly public restroom.

Although, this is one step closer to the transparent aluminum from star trek. Are we sure he didn't get the idea while in San Fran, possibly out there for a wedding or something??

Re:And then come the disclaimers about the uses

[TwistedGreen]

And what about the nuclear wessels?

Re:And then come the disclaimers about the uses

[Ayaress]

I think it would work in public restrooms. From the pictures, it seems to be translucent, not transparent. The picture of the person standing behind the wall only transmitted a shadow through. They already use a lot of frosted glass in restrooms. This stuff is basically frosted glass that can be load-bearing.

Re:And then come the disclaimers about the uses

[Elwood P Dowd]

I've been to a bar that used that fogged glass that turns clear with electric current in some public restrooms.

The bathroom stall door is clear, until you close it, when it becomes opaque.

A bar. A drinking establishment.

Drunk people have a hard enough time operating cigarette lighters.

So, you get to watch drunk idiots take a crap in the bathroom. Boy, does that suck.

Re:And then come the disclaimers about the uses

[irokitt]

AAAGH! (reaches for mental floss/mouthwash)

Re:And then come the disclaimers about the uses

[drsmithy]

I've been to a bar that used that fogged glass that turns clear with electric current in some public restrooms.

The bathroom stall door is clear, until you close it, when it becomes opaque.

There's a pub here in Brisbane with a marginally similar thing - a wall-long urinal that is actually a two-way mirror. You can see one of the beer gardens through it, but from the outside it's just a wall.

Drunk people have a hard enough time operating cigarette lighters.

On that note, in the same toilet, the sinks don't have taps. Instead, there is a concealed panel at about knee height that you push in with your knee to get the water flowing. The number of people who can't figure out how to get the water to go is enormous, and I must admit I only figured it out by accident by leaning against it looking for an "electric eye" somewhere near the spout.

So, you get to watch drunk idiots take a crap in the bathroom. Boy, does that suck.

Crikey, I didn't think anyone was brave enough to back one out in a *pub toilet*, no matter how brave.

In a related story

[AtariAmarok]

In a related story, Packard Bell has anounced that the screens on its new portable computers will use this material. It will replace the current solid-lead screen. They are hoping to get their laptop weight below 68 lbs for the first time.

Translucent Concrete

[shaka999]

While this is a cool idea its not that original

http://www.economist.com/science/tq/displayStory .c fm?Story_id=779421

Bill Price's version actually sounds like it lets through more light but is also harder to work with.

Re:Translucent Concrete

[jc42]

It's a much, much older idea.

Before the 20th century made artificial lighting cheap, it was common for the holds of ships to be illuminated by light coming in through a lot of thick lenses that were embedded into the deck. The lenses were usually roughly pyramidal in shape, with the point down of course. Holes would be drilled in the deck, and then shaped so that the lenses would fit into them flush with the deck. You can see a lot of these in maritime museums these days, as well as in the decks of some of the historical ships in a few harbors.

Of course, they didn't transmit any sort of image. But you wouldn't want them to, really. They just has to be translucent and tough enough to take all the beating they got from above.

Of course, people also included glass bricks in walls for the same purpose. They're still for sale.

Invisible Concrete

[AtariAmarok]

I've got a better idea: Invisible Concrete! In fact, I'll build you an entire skyscraper of invisible building materials for half the cost of a conventional building.

Since the stuff does take a long time to properly cure, I'll have to request that you stay off the premises until this is complete.

In fact, if you venture past the "Caution: Invisible building construction zone tape", it will result in the immediate disintigration of the building, and I will not be held liable for the loss. (This disintegration process is silent and harmless: it is like nothing happened at all).

I'll take payment in advance.

Re:Invisible Concrete

[GerritHoll]

Finally the penultimate solution to terrorism - what you can't see, you can't blow up either ;-)

(the ultimate solution would of course be to simply rid the universe of all intelligent life forms, so in the end terrorism destroys itself)

Re:Invisible Concrete

[Ch_Omega]

If you want matching clothes, I'll get them. They're more than fit for an emperor.

This isn't new.

[andy666]

GE developed a similar thing in the 70's, but didn't think there was a market for it. I imagine that their patent ran out...

Re:This isn't new.

[tiburon666]

GE's idea although similiar in concept was drastically different. Their idea was to use special glass, which would change its level of transparency based on an electrical current which ran through it. This idea was later modified and is now found in the common-place eyeglasses which automatically become more opaque in the light.

I still want...

[monopole]

Transparent Aluminum

Re:I still want...

[kawika]

Transparent aluminum? Don't you read Slashdot?

It's a set-up.

[jafuser]

the light-transmitting concrete that is set to hit the market this year

Nice. Very subtle.

Unanswered question

[El]

What are the heat-transmittal properties of this material? Is it a better or worse insulator than glass blocks?

Re:Unanswered question

[Anonymous Coward]

for a first-order approximation (assuming isotropy), try the old Rule of Mixtures:

k=(ki*xi)+(kj*xj)+...(kn*xn)

where:
i, j, ...n are the components,
k is the property (in this case, thermal conductivity)
and
x is the fraction of the different components.

assuming:
k(e-glass) ~1.0 W/mK
k(concrete)~1.28 W/mK
k(air) ~0.025 W/mK

if the concrete block is 45% glass, 55% concrete, it has a thermal conductivity of (isotropic assumption) ~1.154 W/mK
assuming that the glass brick is hollow, and ~50% solid glass, it has a thermal conductivity of ~0.5125 W/mK.

Re:Unanswered question

[El]

But, couldn't you make the translucent concrete hollow too? Since the thermal conductivity of concrete isn't too different from that of glass, this would be a great replacement for glass block walls... perhaps more expensive, but a hell of a lot stronger! Plus it can be cast into arbitrary shapes -- think round shower enclosures... Complete with skylights.

But it's anisotropic

[dpilot]

So you'd only be able to see through the pillar in one direction, and nothing 90 degrees from that. I know you weren't being serious about the parking garage thing, after all there's the steel inside the concrete of the pillar, but there may be some interesting ways to exploit the anisotropy.

Re:But it's anisotropic

[Anm]

Just because there is steel in the middle of the pillar does mean you can circle the steel with the fiber optics. I'm sure that makes the production orders of magnitude more complicated, but it would probably work.

Anm

Re:But it's anisotropic

[jovlinger]

So make round pillars with the fibers laid out so that they always go perpendicular to the surface tangent.

You could put a steel pillar in the middle -- as long as the fibers go around it.

Re:But it's anisotropic

[dpilot]

But why bother?

Transparent Aluminum

[s2k-go]

I'm still waiting for my transparent aluminum.

Beam me up Scotty.

problem is

[WormholeFiend]

modern construction (apart from some cheap warehouses) doesnt use simple concrete walls.

in a modern building you need insulation, electrical wiring, plumbing, etc.

I only see this kind of concrete being used as part of a specific decoration or artistic scheme.

The first thing I thought of when I saw this was, this could make a very interesting above-ground pool.

Besides, if you are looking at getting more light from the Sun into your building/house/whathaveyou, a friend of mine who is studying in photonics mentionned that a lot of people are working on optic fiber networks that would do just that, from a solar collector outside, to light fixtures inside.

Re:problem is

[codejester]

Ohhh ya, thanks. All of a sudden I want an above ground pool! arg...

Re:problem is

[R.Caley]

I only see this kind of concrete being used as part of a specific decoration or artistic scheme.

If they can make it on-site it could make solid light pipes whcih could make it easier to get daylighht around buildings because the pipes can be structural.

Finally...

[JMZero]

I can have a glass house, and throw stones with impunity.

What about water and air leakage?

[enosys]

I don't think concrete sticks to glass. Do they add something or somehow treat the glass so that it sticks or seal the sides? Otherwise I think you'd get air and water leakage. I'm not sure if the air leakage would be a problem but water leakage probably would. If the outside got wet capillarity would suck some water into the wall. Eventually you'd probably have mold growing on and even in the wall.

Re:What about water and air leakage?

[SdnSeraphim]

I think the kind of fibre optic cable they would use is the kind made from some form of plastic rather than glass fibre.

Re:What about water and air leakage?

[enosys]

The article repeatedly says that it's glass, eg.

...thanks to an embedded array of glass fibers can display a view of the outside...

Re:What about water and air leakage?

[Ayaress]

The article says they're glass, but they're probably pretty fine strands. Once they're in the concrete, even if the concrete doesn't stick well, just the friction along the length of the fiber optic strand would probably be more than their tensile strength, so if you tried to pull one out, it would snap. As for air and water leakage, it's concrete. It's not exactly a great material for keeping water out. Just ask anybody who lives in Micighan or Louisiana and has a basement.

Re:What about water and air leakage?

[pclminion]

I don't think concrete sticks to glass. Do they add something or somehow treat the glass so that it sticks or seal the sides?

Concrete releases heat as it sets. As it cools, it will contract slightly and grip the glass fibers. Glass might not "stick" to concrete, but anything will stay in place if you squeeze it hard enough.

Ulexite / TV Rock

[drivers]

This reminds me of Ulexite ("TV Rock"). It's a mineral made of fibrous crystals that work similar to fibre optics. In this case, the guy made a rock full fibre optics.

Before that, you must join the rest of the world

[Anonymous Coward]

by adopting the metric system, and adding an extra "i" to "aluminum".

Next step...

[Anm]

Automate the construction of the homes with this.

ST-IV

[jannesha]

Anyone else thinking: 'transparent aluminum' ?

would probably work

[dpilot]

But I doubt anyone would bother. If you're going to custom-lay fibers around the steel, they could also be layed in both directions, and take care of my anisotropy. Then we'd come up with a steel pillar that would do a *really good* job of showing shadow shapes.

Re:would probably work

[zero_offset]

Large steel beams with largish holes in it would probably be cheaper.

The house of the future - again

[texchanchan]

See also the Glass Center at the 1939 World's Fair. The house of the future would be light inside because glass bricks would take the place of brick which would of course be totally obsolete by the year 2000.

Next in line...

[marquis111]

Slow Glass!

transparent walls

[slobod]

Some folks already use these walls when they play quake....

They call it...

[Anonymous Coward]

saphire. Get over it. Star Trek is gay, lame, and retarded.

here's another (practical) potential application

[Anonymous Coward]

Fiber Optic Colorimetry Technique For In-Situ Measurement Of Corrosion In Civil Structures

Source: Experimental Techniques Publication date: 2004-01-01 Arrival time: 2004-03-11

Printable, Transparent Houses

[MrScience]

Wow, when coupled with this technology, things could get really interesting!

A robot for "printing" houses is to be trialled by the construction industry. It takes instructions directly from an architect's computerised drawings and then squirts successive layers of concrete on top of one other to build up vertical walls and domed roofs.

Breakage/Stress detectors?

[quinkin]

I remember seeing an optic fibre array that was used to detect curvature and provided early detection of micro-fractures. From memory it used "circular scored" optic fibres for the measurement section and measured the diffraction(?) of the resultant light.

It seems that this could be a big "value add" for embedded concrete - Having a realtime stress diagram of a building would be invaluable in some locales (san fran, kobe, etc).

Q. (In the quest for proof of prior art).

Please learn how to use links.

[Anonymous Coward]

Please learn how to use links.

<a href="http://www.economist.com/science/tq/displayS tory.cfm?Story_id=779421">Bill Price's version</a> actually sounds ...

yields: Bill Price's version actually sounds ...

Nope, you're the first!

[keller]

Except this
and this
and probably 10bn other /.'ers before them ;-)

Forget the concrete

[barzok]

I demand transparent aluminum!

Re:Forget the concrete

[GlassMaster]

Transparent aluminum can be achieved by oxidizing the aluminum to alumina, as is the case with saphire.

The intensity of the light

[Stevyn]

Any photographer knows that the intensity of sunlight is far far greater than the light found in a house. Some light would still seep through, but unless you have a thousand watt light spotlight in your living room, you should be fine.

Extend this idea...

[Anonymous Coward]

Here is a concept...make the glass fiber strands bigger or hammer them out into a flat surface to let more light in.

Maybe even add a latch and some way to move the 'fiber' up and down to let air in. Then you'll have a product everyone will want in their home. And my guess is that it will be cheaper and the surrounding materials will provide all the strength needed.

Leakage and Strength

[nuggz]

First, concrete isn't watertight, all basements leak. Generally they don't leak fast enough to be a problem, it just evaporates away.

If the concrete doesn't stick to the glass, you end up with a weaker product.

The key part of composite materials is that unless the bond between the members is strong you don't end up with ideal performance. In the worst case you end up with the properties of one part (like the concrete) at reduced cross sectional area, and a large number of stress concentrations.

Really better than glass blocks?

[pla]

Perhaps someone more civil-engineeringly inclined than myself can answer this...

We already have exceedingly strong hollow glass blocks available for construction. Perhaps not quite as strong as cast concrete, but I've seen three-plus-story walls made entirely from them, so certainly good enough to use for a large portion of your typical two-story house.

Additionally, judging by the pictures at the linked site, this concrete doesn't really transmit all that much light... More like a (closed) window shade, than a window.

So, what would a person actually use this stuff for? I'll give it a few points for coolness, but from every angle I can think of, some other material seems better suited to the task.

Any ideas?