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Iron Alloy Could Create Earthquake-Proof Buildings
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!"
Original article, after following three backlinks: http://uk.reuters.com/article/idUKTRE62I4AE20100319
Here's a page with a bit more detail. 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.
Sigs are too short to say anything truly profound so read the above post instead.
Earthquake-Resistant!
http://www.physorg.com/news3985.html
Even the beams being put into bridges are concrete because they are stronger and lighter than metal.
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.
http://lkml.org/lkml/2005/8/20/95
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.
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.
Living in Chile