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Iron Alloy Could Create Earthquake-Proof Buildings

samzenpus posted more than 4 years ago | from the shake-all-you-want dept.

Technology 107

separsons writes "Researchers at Japan's Tohoku University designed a new shape memory metal alloy. The super elastic iron alloy can endure serious stretching and still return to its original shape. The scientists say that once optimized, the material could be used in everything from braces to medical stents to earthquake-proof buildings!"

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107 comments

So far removed from the original article (5, Informative)

nickersonm (1646933) | more than 4 years ago | (#31607492)

Original article, after following three backlinks: http://uk.reuters.com/article/idUKTRE62I4AE20100319 [reuters.com]

Re:So far removed from the original article (4, Informative)

Mindcontrolled (1388007) | more than 3 years ago | (#31607834)

Actually - reuters mentions the really original paper, which is here [sciencemag.org] , in this weeks Science edition.

Re:So far removed from the original article (-1, Troll)

Anonymous Coward | more than 3 years ago | (#31607848)

You're a fucking Johnny-come-lately. You should have posted a nigger joke instead.

Re:So far removed from the original article (0, Troll)

L4t3r4lu5 (1216702) | more than 3 years ago | (#31608678)

Actually, if you really want to get back to the source, it was all His [wikipedia.org] idea.

Hmmm... Funny or Troll... PLACE BETS NAO!

Re:So far removed from the original article (-1, Offtopic)

Anonymous Coward | more than 3 years ago | (#31609010)

You will definitely get Funny if you state Cthulhu instead.

Re:So far removed from the original article (2, Insightful)

Nyder (754090) | more than 3 years ago | (#31609836)

Original article, after following three backlinks: http://uk.reuters.com/article/idUKTRE62I4AE20100319 [reuters.com]

So tired of the "news" sites that can't even link the original source anymore.

I hit the source link and goes to someones blog with a source link to someone else's blog, that might have the original story.

You telling me, your in such a hurry to post it, that you can't bother to go back the 2 links for everyone?

What even cracks me up more, is when a site I go to lists slashdot as the source. lol, slashdot isn't a news source, it's a news regurgator.

TFA short on details (4, Informative)

wizardforce (1005805) | more than 4 years ago | (#31607504)

Here's a page with a bit more detail. [metapress.com] These alloys are of similar composition to stainless steel and tend to have very high levels of Nickel and a little Chromium tossed in for good measure. Shape memory alloys work by utilizing a crystal structure phase transition that causes stress in the alloy to re-align which basically is responsible for the shape change.

It will be expensive and unused (1, Interesting)

BadAnalogyGuy (945258) | more than 4 years ago | (#31607506)

Modern construction techniques and materials are actually really good. Except for the occasional airliner or two crashing into them, our buildings are able to withstand tremendous strain. These days, most new buildings in the modern world are built with these techniques and materials. Flexible yet firm. Light yet strong. We've come a long way in this respect.

But we also have the money to build these things. Take a look at some recent tragedies caused by earthquakes. Bam, Chile, etc. These aren't places that have especially tall buildings. In fact, most of their buildings are slapped together walls with heavy roofs. When the ground starts shaking, these things are death traps.

So this new technology is great, but don't expect to see it saving lives in the Third World. Those places will continue to lose people by the thousands every time a 6+ magnitude earthquake hits. They just don't have the money to build correctly.

Re:It will be expensive and unused (4, Insightful)

jgardia (985157) | more than 3 years ago | (#31607720)

In Chile the earthquake was 8.8, and the deaths were about 500 (about half because of the tsunami).
By law, you have to build everything to withstand an 8. I'm not sure if you've been in an earthquake, but I remember perfectly the one in 1985 (was magnitude 8), and it was damned strong. The last one was 6 times bigger.
Anyway, we've been making anti sismic constructions for decades, and you can see the result in the last earthquake. Very few builings falled (most of them old), and low casualties. There have been also 10+ replicas over 6 since the earthquake (also a 7.2).
So, please when you want to be pedantic and tell us "Those places will continue to lose people by the thousands every time a 6+ magnitude earthquake hits", please do your homework first. We usually have a 6+ at least once a year.

Re:It will be expensive and unused (0)

Anonymous Coward | more than 3 years ago | (#31607754)

I didn't see him mention Chile.

Re:It will be expensive and unused (0)

Anonymous Coward | more than 3 years ago | (#31607768)

Then look again. Quote:

Take a look at some recent tragedies caused by earthquakes. Bam, Chile, etc.

Re:It will be expensive and unused (1)

mlush (620447) | more than 3 years ago | (#31608276)

(In Chilie) By law, you have to build everything to withstand an 8.

In Chile I suspect it not so much a case of Law, its more akin to natural selection. :-)

Re:It will be expensive and unused (1)

Anonymous Coward | more than 3 years ago | (#31608632)

No, it is law, Chile is exceptionally prosperous for the region and with prosperity come building codes.

Re:It will be expensive and unused (5, Interesting)

cenc (1310167) | more than 3 years ago | (#31608912)

Chile is not Haiti. It is not even California. The building codes are law, and they are enforced. However, there is something to the natural selection thing, but not the way you mean.

Thousands of buildings went through the 8.8 earthquake with little more than a few cracked windows. It looks like total building collapse amounts to 1 building that litterally fell over on its side, and about 100 or so others that failed by design. The ones that failed on a wide scale where 200+ year old adobe houses (mostly one and two story structures). Those adobe structures did survive to some degree because they had never taken a full earthquake. The big ones had always been north or south of the 7th and 8th regions that got hit the hardest by this quake.

The death however was not really caused by the earthquake, but by the tsunami waves that came 3 hours apart. The navy screwed up by lifting the alert too soon, and people started returning to the beach.

My office building (15 floors), took an 8.0 about 200 miles from the epicenter. We lost a couple glass doors when the metal frame flexed, a few cracks, and one broken water pipe on a floor. It was built about 10 years ago.

No one even gets up and leaves the building anymore for anything under a 6.0 around here.

Re:It will be expensive and unused (1)

PingPongBoy (303994) | more than 3 years ago | (#31615748)

We usually have a 6+ at least once a year.

Yeah? Isn't it ... Time to get out of Dodge!

They say what doesn't kill you makes you stronger, but Russian roulette doesn't really make you stronger.

Re:It will be expensive and unused (2, Interesting)

mjwx (966435) | more than 3 years ago | (#31607730)

So this new technology is great, but don't expect to see it saving lives in the Third World. Those places will continue to lose people by the thousands every time a 6+ magnitude earthquake hits. They just don't have the money to build correctly.

Sorry BAG but I have to disagree with you here. Plenty of third world nations have (or potentially) heaps of money, nations like Indonesia have lots of oil, Thailand has massive exports with food and finished products.

The problem is twofold, 1. Skills Shortage. The education systems in the third world do not produce many skilled labourers like Electricians, Fitters, Boilermakers and Architects and certainly not to the standards of the western world. 2. Politics, corruption at all levels as well as lack of standards and standards enforcement means that buildings that are clearly unfit or will fall down as soon as a strong wind blows are built. Going back to the labour situation, in the west the government forces you to use certified architects and electricians (enforcing standards) but they cost double a basic labourer, in the third world a few units of the local currency into the right hands and you can employ barely trained workers for any complex task or pretty much whatever you want.

Imagine for a moment how rich Sierra Leone would be without all that war, a dictators wealth would rival that of Carlos Slim or the sultan of Brunei, a non dictatorial government would have turned it into the Monaco of Africa.

Re:It will be expensive and unused (2, Insightful)

sensei moreh (868829) | more than 3 years ago | (#31608652)

Chile is not Haiti - at least I don't think it is; I've never been to either one. However, the death toll in Chile was surprisingly low for a magnitude 8.8 earthquake. Sure, older buildings collapsed, just as they do in California and Japan when large earthquakes strike. The death toll in the 1989 Kobe, Japan earthquake was about 5100; more than five times that of the Chilean quake. And Japan is seen as a leader in building earthquake-resistant structures. Obviously, Chile has done something very, very right to keep the death toll so low.

Re:It will be expensive and unused (1)

rubycodez (864176) | more than 3 years ago | (#31610710)

actually, those particular buildings the airliners hit were very flimsy cost-reduced crap compared to comparable ones made with normal construction techniques. Normally you'd ruin a perfectly good airplane. Real "skyscrapers" can withstand tremendous strain including the airliners.

Re:It will be expensive and unused (1)

dr2chase (653338) | more than 3 years ago | (#31611938)

Do note, it was the fire that did it, not the impact of the airplanes.

And come to think of it, how does this nifty new metal behave when it is hot? How does it hold up as far as corrosion goes?

Re:It will be expensive and unused (1)

rubycodez (864176) | more than 3 years ago | (#31618302)

Impact plus fire would be more accurate. And the thicker and more fire-insulated a structural member, the longer it will take to fail. Part of the "cost reduced crap"-iness I was referring to was use of struts from inner to outer wall, and beams with minimal (though just within regs for the time) fire insulation.

Proof? (4, Insightful)

Elgonn (921934) | more than 4 years ago | (#31607512)

Earthquake-Resistant!

Re:Proof? (2, Funny)

Khyber (864651) | more than 3 years ago | (#31607726)

make a plane out of this stuff and put it in the air, as long as it is in the air, it's earthquake-proof 100%.

Re:Proof? (1)

MrNaz (730548) | more than 3 years ago | (#31608444)

Moving on to other news, an aircraft has been destroyed in a freak accident where an earthquake triggered a volcanic eruption and the resulting sudden plume of magma spewed upwards directly hitting the aircraft and causing it to crash. Witnesses reported hearing a deep grumbling sound from the shaking earth, with some claiming they heard the words "your move, puny humans" emanating from the ground.

Re:Proof? (1)

dgatwood (11270) | more than 3 years ago | (#31614892)

<insurance_adjuster>Hey, we said earthquake-proof. We didn't say it was volcano-proof. Besides, you'll specifically note in the fine print that we disclaim responsibility for all damages due to acts of God.</insurance_adjuster>

Flexible concrete is better and we already have it (5, Interesting)

JDmetro (1745882) | more than 4 years ago | (#31607530)

http://www.physorg.com/news3985.html [physorg.com]
Even the beams being put into bridges are concrete because they are stronger and lighter than metal.

not they aren't (4, Insightful)

YesIAmAScript (886271) | more than 4 years ago | (#31607674)

Concrete is stronger under compression, but it's so lousy under tension that you put metal into it to take that strain. And how metal is supposed to be stronger than metal I dunno.

And lighter than metal? Not yet. Tell me when you see stadiums with concrete roofs.

Also how you're going to resist an earthquake with only compression I dunno.

Concrete is very good at some things, others not so much.

Personally I don't like formwork buildings. I know they're really common now I know, and you really can do so much with it I see why architects are interested, but right no I just feel like architects haven't figured out how to make appealing buildings with it yet. Right when we finally broke out of the International style with skyscrapers, it feels like formwork has knocked us back a bit.

Re:not they aren't (2, Informative)

Khyber (864651) | more than 3 years ago | (#31607734)

'Tell me when you see stadiums with concrete roofs."

What sort of stadium? I know of several marine life stadiums with concrete roofs. I can think of one in Florida, one in Washington, and one in Mississippi. I'm sure there are several in Oregon. In fact, the ENTIRE STRUCTURE for these stadiums is solid concrete.

I mean for sporting events (1)

YesIAmAScript (886271) | more than 3 years ago | (#31607766)

You know, a regular-type stadium for football or basketball or whatever. Never heard of an aquarium being called a marine life stadium before.

If I were building a building designed to hold brine and thus a salt-tinged atmosphere, I'd be tempted to use concrete too. The aquarium in Monterey for example is entirely made of concrete.

But every sporting-type stadium I know uses a roof made of steel or fabric. Why? Because it's light. The only weight it has to hold up it is own, so the less weight the roof can have, the less material you need. And steel uses a lot less material than concrete for these things. Even if you had concrete spans (possible although difficult), it'd be corrugated steel actually forming the roof to save weight. The fabric roofs are even lighter, although in that case the air inside is actually supporting the roof, not the roof structure itself.

Re:I mean for sporting events (0)

Anonymous Coward | more than 3 years ago | (#31607776)

The saddledome in Calgary has a concrete roof: http://en.wikipedia.org/wiki/Pengrowth_Saddledome

Re:I mean for sporting events (1)

zippthorne (748122) | more than 3 years ago | (#31608538)

The largest unreinforced concrete dome is about 140 ft wide and has stood for nearly two thousand years. Not nearly large enough for a football field, but not entirely hopeless, either.

Re:I mean for sporting events (3, Funny)

fuzzyfuzzyfungus (1223518) | more than 3 years ago | (#31608622)

True; but that one is actually held up by gravity's fear of the Roman Empire. As soon as the laws of nature learn that the Romans are gone, that sucker is coming down...

Re:I mean for sporting events (1)

moosesocks (264553) | more than 3 years ago | (#31610466)

The Washington Coliseum [blogspot.com] in DC has a thin-shell concrete roof supported by an odd concrete exoskeleton [flickr.com] . The construction method is known as the Zeiss-Dywidag [monolithic.com] process.

The method was somewhat popular in the early 20th-century, but seems to have fallen from favor after WWII. That said, the Coliseum is still standing, despite a great many years of abandonment and deliberate abuse. That said, it's a prime target for historical preservation, given that it's an architectural oddity, has a rich history (the Beatles played there!), and is in dire need of repair.

Re:not they aren't (2, Informative)

Bigjeff5 (1143585) | more than 3 years ago | (#31607812)

The largest concrete dome in the world is in a church about 400+ years old. It is large, but not even close tothe size of conventional buildings, let alone sports stadium. Concrete is great at some things, but not everything.

Most likely use for memory-steel would be as the internal reinforcement in concrete structures, similar to what they already do, just better.

Re:not they aren't (3, Informative)

MrNaz (730548) | more than 3 years ago | (#31608454)

No, it won't be better. Think about why the metal is there. If the metal in the concrete is too flexible, the greater brittleness of the concrete will result in the concrete cracking and breaking due to the metal not providing sufficient support.

Re:not they aren't (1, Informative)

Anonymous Coward | more than 3 years ago | (#31610152)

Well there was the King Dome in Seattle. As I remember the concrete roof was pretty hard to bring down when its time had come. I believe Seattle WA is considered earthquake country.

Re:not they aren't (1)

JDmetro (1745882) | more than 3 years ago | (#31607816)

http://www.lightconcrete.com/cellularconcrete.html [lightconcrete.com]
http://forum.skyscraperpage.com/showthread.php?t=122219
http://www.litracon.hu/
I have several years experience as a concrete finisher btw.

Oh and there is something called pre-stressed (2, Informative)

JDmetro (1745882) | more than 3 years ago | (#31607830)

tendons and post stressed tendons and they use them in concrete beams.

In pre-stressed, it's steel doing the work (1)

YesIAmAScript (886271) | more than 3 years ago | (#31607892)

The tensioners are steel. So again, it's metal doing the work here, it's not going to be stronger than metal, it is metal.

Concrete is great for stacking stuff up. It can carry a lot of weight. But it isn't light and it is useless under tension, so metal (almost always steel) does that work for it.

Re:not they aren't (1)

Rhys (96510) | more than 3 years ago | (#31609774)

Concrete dome sports arena... you mean like the UofI Assembly Hall? Just sayin'.

http://en.wikipedia.org/wiki/Construction_of_Assembly_Hall_(Champaign) [wikipedia.org]

very cool, and it does support itself mostly! (1)

YesIAmAScript (886271) | more than 3 years ago | (#31618526)

Unlike the Saddledome which is larger, but is really held together by steel cables with concrete panels just basically creating an enclosure, not the load bearing structure.

I found out about so many interesting structures by spouting off incorrectly like a bonehead!

Re:not they aren't (1)

JustABlitheringIdiot (1773798) | more than 3 years ago | (#31609892)

Concrete is stronger under compression, but it's so lousy under tension that you put metal into it to take that strain. And how metal is supposed to be stronger than metal I dunno.

Absolutely correct here, concrete has very little tensile strength and it is typically reinforced in varying degrees depending on the force distribution being applied to the member. In any other sense than being pedantic, it is not a fair statement to say that the steel is what makes it so special. The majority of the section is concrete steel is limited in AASHTO to 4% by area (if my memory serves me correctly). Anything more than that does not help with additional strength and can actually weaken the matrix.
Good question on metal being stronger than metal, I will assume you mean steel, there are numerous grades of steel that are used structurally ranging from 36 ksi to 60 ksi typically some can be even stronger. It depends entirely on the amount of carbon in the steel and the way the nodules are shaped and distributed.

And lighter than metal? Not yet. Tell me when you see stadiums with concrete roofs.

The answer here is that yes they are lighter than steel in a way. The density of concrete is 150 pcf and steel is around 490 pcf. So even though the concrete beams have a larger sectional area they tend to be marginally lighter. This is related to the shape of the beams, steel tends to have a deeper web and concrete a shallower thicker web for the same capacity. Additionally when the concrete beams are heavier, the savings in the reduced height of the abutments more than off sets the downside.

Also how you're going to resist an earthquake with only compression I dunno.

Well that's the funny thing about earthquakes and it is a major area of research around the globe. It has been proven repeatedly that a reinforced concrete wall will survive exceptionally well in an earthquake. The primary reason is the way the waves propagate with the most common form being a vertical movement (this introduces a compression in to the column rather than a shear). The horizontal Rayleigh waves are usually very shallow and introduce a shear movement that is not as great a magnitude as the vertical waves. BTW the measure of the compression strength of concrete is really a measure of the shear strength (think back to Mohr's circles) so as long as there is sufficient shear capacity within the concrete and steel matrix there will be no problem (see above for how its mainly concrete and the claims about steel are just pedantic - I fully expect to see that though, this is /. after all).

Calgary Saddledome: concrete roof on a stadium (1)

wexsessa (908890) | more than 3 years ago | (#31610214)

http://en.wikipedia.org/wiki/Pengrowth_Saddledome [wikipedia.org]
http://www.canada.com/calgaryherald/news/story.html?id=bb367c51-527e-4abc-b61a-39821fa3f0f9 [canada.com]
"Working with British structural engineer Jan Bobrowski, whose firm still lists the Saddledome on its website, the design team came up with the concept of a roof made of precast concrete panels supported by a net of cables. Think of it as a giant tennis racket, a grid of cables, and on this net you drop these concrete panels,"

Re:not they aren't (1)

DerekLyons (302214) | more than 3 years ago | (#31610276)

Tell me when you see stadiums with concrete roofs.

The Kingdome [wikipedia.org] ,

Re:not they aren't (1)

YesIAmAScript (886271) | more than 3 years ago | (#31618504)

Well, I made a lot of mistakes there, but in this case I was sure there was a major concrete dome in the US. And I was sure it was to superdome. But I looked it up, it's steel, so I went ahead and spouted my ignorance on the internet.

I just had the wrong structure, I could have saved myself some embarrassment if I hadn't confused the kingdome with the superdome. They were built at the same time and I just got messed up as to which was which.

Re:Flexible concrete is better and we already have (2, Interesting)

MrMista_B (891430) | more than 3 years ago | (#31607756)

How the hell could you use something like flexible concrete that for braces or medical stents? This new alloy isn't /just/ for earthquakes, you know. And that info's right even there in the summary!

Flexible concrete is worse for medical stents or braces than this alloy. Ridiculously worse.

Re:Flexible concrete is better and we already have (2, Informative)

Space Guerilla (1766806) | more than 3 years ago | (#31607832)

http://www.physorg.com/news3985.html [physorg.com] Even the beams being put into bridges are concrete because they are stronger and lighter than metal.

Correction: Even the beams being put into bridges are bendable concrete because they are stronger and lighter than metal.

More on that Bendable concrete: "Essentially, the fibers create many microcracks with a very specific width, rather than a few very large cracks (as in conventional concrete.) This allows ECC to deform without catastrophic failure" http://en.wikipedia.org/wiki/Bendable_concrete [wikipedia.org]

But before Bendable concrete this is how things were done: There are 3 kinds of forces, Tension, Compression, and Torsion (twisting motion).

Concrete is not "stronger" than steel, it is simply better in compression than steel (it can support more weight). If concrete is in tension beyond the limit, it will break (suddenly and without warning). Concrete is reinforced with steel because the steel complements it. Steel shows signs of fatigue before it breaks when over its limit. Also with changing temperatures, both steel and concrete expand and contract at similar ratios.

Re:Flexible concrete is better and we already have (1)

JustABlitheringIdiot (1773798) | more than 3 years ago | (#31609600)

Correction: Even the beams being put into bridges are bendable concrete because they are stronger and lighter than metal.

ECC - Engineered Cementicious Composite - is NOT used in bridges. Your standard I bulb beams are prestressed concrete. It has high strength concrete in it (compression typically > 5500psi) but it is almost never fiber reinforced.

In fact for that matter the "newer" concrete technologies, ECC, RCC, SCC, to name a few are not widely used in industry. Some projects use them but they are not common.

Re:Flexible concrete is better and we already have (2, Informative)

fnj (64210) | more than 3 years ago | (#31609654)

Concrete is not "stronger" than steel, it is simply better in compression than steel (it can support more weight).

That is wildly incorrect. Concrete is very usable in compressive members, and is used for a variety of reasons (cost being an extremely important reason), but none of the reasons is because it is stronger than steel. High strength concrete is defined by the American Concrete Institute as having greater than 6000 psi compressive strength. Concrete with 12,000 psi strength is used in structures requiring high performance, and represents a slightly higher strength than was thought possible in 1970. You can get concrete of 19,000 psi strength if you want to pay for it.

Regular dirt cheap time honored 1012 carbon steel had a strength of about 50,000 psi. Concrete is not stronger than that, eh? High strength structural steel is at least 80,000 psi. "Maraging" steel's strength is over 200,000 psi and up to 300,000 psi.

Strength to weight ratio is of course what matters, and here concrete looks considerably better because of its low density. In these terms it's close to so-called high strength structural steel, but doesn't even come close to something like maraging steel, and is outperformed by plain old 6061-T6 aluminum alloy.

Buildings will return to their original shape? (1)

John Saffran (1763678) | more than 4 years ago | (#31607538)

From the reuters article:

Omori said the super-elastic iron alloy may also be used for buildings in earthquake prone areas. "This material can be used for buildings in earthquake zones. The buildings are deformed by earthquake, but super elastic alloy can return the building to its original structure," he added.

There's no much detail but somehow I don't think that will happen unless he's also invented a 'super-elastic' concrete ..

Re:Buildings will return to their original shape? (1)

Aerynvala (1109505) | more than 4 years ago | (#31607574)

Re:Buildings will return to their original shape? (1)

John Saffran (1763678) | more than 4 years ago | (#31607686)

Alright smarty pants .. let me amend that statement

"I dont' think that will happen unless he's also invented a 'super-elastic' wood, and glass, and made it super-cheap too"

I threw in super-cheap in just for good measure ;) .. if he achieves all that, then he won't be needing MY congratulations, he'll be too weighed down by filthy lucre to care :D

Re:Buildings will return to their original shape? (1)

the_other_chewey (1119125) | more than 4 years ago | (#31607610)

There's no much detail but somehow I don't think that will happen unless he's also invented a 'super-elastic' concrete ..

Fibre-reinforced concrete already exists. It has pretty amazing properties, a very un-concretelike elasticity included.

Re:Buildings will return to their original shape? (1)

galaxia26 (918378) | more than 4 years ago | (#31607624)

Then why is it still called "concrete". If we're changing that definition, I'm suddenly very off the hook as far as quoting turnarounds at work based around "concrete" numbers.

Re:Buildings will return to their original shape? (0, Troll)

AK Marc (707885) | more than 3 years ago | (#31608052)

Then why is it still called "concrete".

Steel reinforced concrete is called "rebar" or just "concrete." Why should fiber reinforced not carry the same name? You could always call it "fibar."

Re:Buildings will return to their original shape? (1)

delinear (991444) | more than 3 years ago | (#31608708)

Then why is it still called "concrete". Steel reinforced concrete is called "rebar" or just "concrete." Why should fiber reinforced not carry the same name? You could always call it "fibar."

"Fibar" would just get confused with "normal" concrete which, when in a collapsed state, is referred to by the scientific term "FUBAR".

Re:Buildings will return to their original shape? (0)

Anonymous Coward | more than 3 years ago | (#31609234)

Steel reinforced concrete is called "rebar"

It is not.

Re:Buildings will return to their original shape? (1)

crimperman (225941) | more than 3 years ago | (#31610148)

> Steel reinforced concrete is called "rebar"

No. That is the shortened name for the steel reinforcement bars placed within the concrete

Re:Buildings will return to their original shape? (0, Flamebait)

AK Marc (707885) | more than 3 years ago | (#31616464)

That is the shortened name for the steel reinforcement bars placed within the concrete

I think you are confusing it's name with what it's called. "Rebar" isn't the name of that type of concrete, but is what it's sometimes called. You complained about my answer, but then addressed something completely different.

Re:Buildings will return to their original shape? (1)

NotOverHere (1526201) | more than 3 years ago | (#31610750)

Am I the only one that had an image of Beavis and Butthead walking through So Cal while the buildings are flopping and twitching like bobbleheads, all the time the our dynamic duo going "Boioioioioinggggg!"

OMG THIS WAS PROPHESIZED (1)

introspekt.i (1233118) | more than 4 years ago | (#31607646)

By the prophet Ayn Rand in her prophecy Atlas Shrugged! The glorious Rearden Metal has come to save us all!!

i woke my dog up laughing (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#31607676)

at the Ayn Rand "prophet" line. Thanks.

Re:OMG THIS WAS PROPHESIZED (-1, Offtopic)

Anonymous Coward | more than 3 years ago | (#31607838)

Man the loonies sure come out when Rands name is mentioned.
And I say this as a Rand fan who knows that her works are only really understood by a few.
Here's a bit of a shocker that would surprise the book skimmers, the highest value according to Rand is *not* money.

Re:OMG THIS WAS PROPHESIZED (0)

Anonymous Coward | more than 3 years ago | (#31616564)

Here's a bit of a shocker that would surprise the book skimmers, the highest value according to Rand is *not* money.

Right. It's self-interest. Which is sooooo different.

[me rolls eyes]

Flexibility != Ability to Carry Loads (2, Interesting)

Game_Ender (815505) | more than 3 years ago | (#31607706)

What is important for construction is the load before the metal begins to yield. If the material yields very early, it doesn't matter how well it snaps back into shape, because it you won't actually be able to build a structure out of the stuff. Just look at some plastics, they are very springy, but try make anything out of the them, and the entire structure starts to flex and sway.

Short version: A material actually needs some stiffness to be practical

Re:Flexibility != Ability to Carry Loads (1)

Bigjeff5 (1143585) | more than 3 years ago | (#31607836)

Indeed, the reason so many buildings failed in Haiti is because they used substandard techniques - aka no rebar to support the concrete, and they probably didn't cure the concrete properly in a lot of cases as well.

Re:Flexibility != Ability to Carry Loads (1)

crimperman (225941) | more than 3 years ago | (#31610024)

I know what you mean but steel reinforcement does not support the concrete. It adds tensile strength where the concrete needs it. In an earthquake the building may well be subjected to both in quick succession or simultaneously and so the two can fail unless the building is designed to cope with earthquake-type stresses. That costs extra and that is why the buildings tend to fail.

Re:Flexibility != Ability to Carry Loads (2, Insightful)

wish bot (265150) | more than 3 years ago | (#31608180)

The frequency of oscillation is also important.

Very flexible materials may not break, but they can lead to standing waves that amplify to literally tear the structure apart.

Awesome Pictures! (-1, Offtopic)

BobandMax (95054) | more than 3 years ago | (#31607710)

The linked article pictures were totally awesome! You can see right where Godzilla came out of the water, stepped on and kicked buildings! That is the coolest thing I have ever seen!

Why use expensive material for that? (0)

Anonymous Coward | more than 3 years ago | (#31608014)

Dampers have been used for ages to improve building resistance to earthquake and wind motion. It is much cheaper to add/improve a damper system that will counter the effect of the earthquake on the building than to build it/rebuild it with earthquake resistant material.

Furthermore these "advanced materials" are more sensitive to fatigue, something not likely to be seen in a building that is designed with rigid steel beams.

Seems to be a solution in search of a problem.

See http://en.wikipedia.org/wiki/Tuned_mass_damper

At first glance defense applications come to mind (2, Interesting)

bdwoolman (561635) | more than 3 years ago | (#31608038)

Vehicle armor especially.

Body armor maybe -- perhaps too heavy.

Could work in a weave though.

Re:At first glance defense applications come to mi (0)

Anonymous Coward | more than 3 years ago | (#31613148)

This won't be noticeably better at dissipating energy rapidly through the structure. You need to generate massive damage to the structure to dissipate the energy of impact from a bullet in order to make good armor. Phase change alloys bend too easily to do this.

What'd be the final goals? (2, Insightful)

VincenzoRomano (881055) | more than 3 years ago | (#31608226)

In my opinion, in order:
1. save as many lives as possible and
2. save as much stuff (money) as possible

So, a building structure that is capable to remember its original shape is certainly aimed to meet requirement no.2.
But will hardly meet no.1.
Can you imagine a building that's "flexible" enough to make stairs and elevators useless to people trying to get out of it?
And that'd be just the structure. What about the resulting wall rubble?
Maybe making lower buildings with wider streets in cities could help.

Re:What'd be the final goals? (1)

allcaps (1617499) | more than 3 years ago | (#31608500)

It would be better than starting from the ground up again. (assuming its cheap enough in the first place)

Re:What'd be the final goals? (2, Interesting)

crimperman (225941) | more than 3 years ago | (#31609962)

How flexible are you expecting this stuff to be? I doubt it will give us buildings that bend like reeds thus staircases are not going to be bending enough to be useless. More likely it gives a greater flexibility around joints within specific small tolerances. Thus the building core: stairs etc. remains intact for longer and permits a greater number of people to escape. Most buildings are already designed in this way anyway with the core escape zone built to withstand more than the rest of the building.

Re:What'd be the final goals? (2, Interesting)

tomdarch (225937) | more than 3 years ago | (#31610102)

As an architect, I can say that you are thinking about this problem exactly how architects and engineers do, and you've identified most of the critical problems. Along with the fact that "falling stuff inside the building" (e.g. filing cabinets and light fixtures) kill building occupants, fire also kills many people in earthquakes. This "more stretchy" steel won't necessarily help with either of these. Most of our systems for limiting the spread of fire (like drywall, spray-on-fireproofing and concrete block interior walls) are very much "not stretchy" and will crack/crumble when the building frame deforms, leaving them useless for limiting the spread of smoke and fire when the shaking stops. This stuff may turn out to be great, but it won't make much of a difference any time soon, and it doesn't sound like it would be particularly "revolutionary."

Re:What'd be the final goals? (1)

dr2chase (653338) | more than 3 years ago | (#31612978)

Maybe all the gas pipes and electrical conduits should be made of this stuff. That's what you want to bend and wiggle, maybe get deformed, but not break.

Right, so instead of ... (1)

Turzyx (1462339) | more than 3 years ago | (#31608662)

the building shaking, the building will flail about in the air tossing the inhabitants around like a washing machine. There has to be some stability in the structure to allow people to safely exit.

I'm sure this approach will protect the buildings, but falling objects and/or people are one of the main causes of injury in an earthquake. I'm not sure this is better.

Cars! (0)

Anonymous Coward | more than 3 years ago | (#31609058)

How about putting this metal in cars? Never have a totaled vehicle again!

"earthquake-proof"? yeah, right (1)

jsepeta (412566) | more than 3 years ago | (#31609148)

i seriously doubt you can fool mother earth during a 7 or 8 into believing that your building is flexible enough to straighten up 100%. once a slinky gets bent, it never works the same and it's practically impossible to fix it.

Good for building, maybe not good for you (1)

SEWilco (27983) | more than 3 years ago | (#31609360)

So the metal can bend, but goes back to its original shape. So the building can spring back to its original shape after the walls flop down and squish you. Yup, that's good for the building.

It's not THAT flexible (1)

ReedYoung (1282222) | more than 3 years ago | (#31615380)

The hard science: [sciencemag.org]

Shape-memory alloys, such as Ni-Ti and Cu-Zn-Al, show a large reversible strain of more than several percent due to superelasticity. In particular, the Ni-Ti-based alloy, which exhibits some ductility and excellent superelastic strain, is the only superelastic material available for practical applications at present. We herein describe a ferrous polycrystalline, high-strength, shape-memory alloy exhibiting a superelastic strain of more than 13%, with a tensile strength above 1 gigapascal, which is almost twice the maximum superelastic strain obtained in the Ni-Ti alloys.

The next challenge for materials scientists will be an intermediate elasticity material for walls. The ability of the frame to flex several percent under the force of an earthquake is a good thing, full stop. But then the walls will need to be flexible enough not to be torn off the flexible frame, yet firm enough not to deform, and thereby shatter, every single window. Granted, broken windows will kill and seriously injure fewer people than falling buildings, but engineers will want to minimize window breakage as well. It sounds like a fun problem to try to solve.

"Say, that's a nice bike..." (0)

Anonymous Coward | more than 3 years ago | (#31616684)

Awesome, I can fabricate me a T1000 for those days my boss is is being a tool.

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