The Future of Earthquake-Proof Buildings


Thanks to Brilliant for supporting this whole
week of SciShow! You can learn more at Brilliant.com/SciShow. [ INTRO ] Nature has an entire suite of disasters at
its disposal, and some are more difficult to predict than others. Like earthquakes. Earthquakes are basically impossible to predict
with any real certainty, so populations living on or near fault lines
are constantly on the lookout for the next big one. Still, it’s not like we’re not twiddling
our thumbs, just waiting for it to strike. Engineers have already developed some pretty
amazing inventions that help protect buildings during ‘quakes, and they’re working on
more. Here’s what they have in their arsenal now,
along with a sneak peek of what’s on the horizon. Today, there are a few main ways we try and
protect buildings from earthquakes. One is to keep buildings from shaking side
to side as much as possible, and that can be done in several ways. Many huge skyscrapers utilize massive swinging
balls, a.k.a. tuned mass dampers. They’re large pendulums placed high inside
buildings, and they sway in response to any movements the building makes. That counteracts whatever is happening outside. The most famous building with one of these
is probably Taipei one-oh-one in Taiwan. For shorter buildings, engineers often choose
a different route: They isolate the base of the building from
the ground using a system of rubber and lead that serves as a shock absorber. A major airport in Turkey uses this method, and it’s one of the largest seismically
isolated buildings in the world. It uses three hundred separate isolators that
can reduce the side to side ‘umph’ the earthquake puts on it by eighty percent. Which is impressive. Still, while tuned mass dampers and shock
absorbers are great, they’re not perfect. So engineers are also exploring new options
to really step up their game. Some of this research builds off of existing
ideas. For example, in two thousand fifteen, one
group proposed a new system called vibrating barrier, which is like a super-strong version of a
regular shock absorber. You start with a weight held in place by springs. Then, you stick it all in a box, and bury
that box near a building’s foundation. When an earthquake comes along, the weight
gets jostled around, and in doing so absorbs the vibrational energy
that would otherwise hit the building. This kind of tech would be perfect for buildings
you can’t modify, like historical landmarks. But it isn’t ready to go primetime yet. You still have to calibrate the system to
absorb a certain frequency, which is specific to each building. That’s because, depending on a building’s
mass and what it’s made of, there are going to be some frequencies that
make it vibrate more than others. So, you’d need to use springs of a specific
stiffness. More massive buildings will also need more
massive dampers. Still, models suggest this could do a lot
of good: Some experiments report that this system could reduce the amount of acceleration
a building is subjected to almost ninety percent. Also, they could protect multiple buildings
at once! So they’re totally worth researching further. Of course, there are a thousand ways to solve
a problem, so other teams have approached this earthquake challenge a little differently. For example, one major field of research involves
investigating how to strengthen the buildings themselves. Some of that involves using fancy new construction
ingredients, like carbon nanotubes. But there’s another way to go about it,
too. Like, in twenty eighteen, one team at Purdue
announced that they had been 3D-printing cement paste into specific shapes and patterns to
improve the concrete’s response to earthquakes. They’re calling these patterns “architectures”,
and they’re capable of carefully directing pressure that could induce cracks. So, even though damage does happen to the
structure, the /overall/ damage is minimized. What’s really cool, though, is that these
architectures are inspired by nature — specifically, by the shells of arthropods. For example, the mantis shrimp has a giant
claw to smash prey at a blinding speed. To avoid having this claw develop one huge
crack, it’s structured in such a way that microcracks
form in a specific helical pattern that distributes the pressure over a larger area. That makes the claw less brittle overall. And now, those helical patterns are being
used in construction. Admittedly, this research is pretty new, so
it’s going to take some time to figure out exactly if and/or how it can be incorporated
into future buildings. But it’s pretty awesome that our solution
to a natural disaster could come from nature itself. Now, vibrating barriers and nature-inspired
materials are cool, but they might seem pretty standard in the
engineering world. So if you’ve been holding out for a really
weird, wonderful example… we have one of those for you, too. I’m talking earthquake invisibility cloaks. Here, you have a series of vplastic rings
built into the foundation of your building of choice. Each ring has its own specific stiffness and
elasticity to absorb a certain frequency of wave. When an earthquake hits, the rings deform
and deflect some of the ‘quake’s energy along themselves, moving that energy around the building so
that the people inside never feel a thing. Basically, the building becomes “invisible”
to earthquakes. I mean, this isn’t great news for the next
building over if it doesn’t have its own protection, but I guess this technology lives in a world
where it does. The more rings you have, the more frequencies
you can cover. And you don’t necessarily need a hundred
of them, either — you just need enough to take care of the most
abundant frequencies, and the ones the building is most sensitive to. Also, as a huge bonus, these rings don’t
have to be massive. For a ten meter-wide building, each ring would
only have to be about ten centimeters thick. This technology started getting attention
around two thousand nine, though, so there are obviously a few things to work out before
it starts popping up in the real world. But like the other developments we’ve talked
about, it is really promising. At the end of the day, the Earth isn’t going
to stop throwing earthquakes at us. But these kinds of innovations mean that,
maybe one day, we won’t have to worry too much about the next big one. Earthquakes aren’t the only challenge engineers
have to tackle, though. Their work involves everything from traffic
to suspension bridges — and if you want to learn more about those
fields, you can check out the Infrastructure chapter in the Physics of the Everyday course
from Brilliant. It even has a whole section about skyscrapers. One thing I learned was that many skyscrapers
have a center of mass that’s below the surface. That helps stop them from falling over, and
it’s cool to think about. This course has plenty of other facts, diagrams,
and interactive quizzes, too, so whether you want to learn about skyscrapers
or airplanes, there’s probably something there for you. Also, if you download Brilliant’s iOS app,
you can get their courses offline! To learn more, you can head over to Brilliant.org/SciShow. And if you want to get yourself an annual
Premium subscription, the first 200 people to sign up at that link will get 20% off! [ outro ]

100 thoughts on “The Future of Earthquake-Proof Buildings

  1. SciShow is supported by Brilliant.org. Go to https://Brilliant.org/SciShow to get 20% off of an annual Premium subscription.

  2. There were some papers suggesting that the Romans may have built many of their large structures with some measure of seismic invisibility.

  3. 04:20 How to stop excessive vibrations: A series of plastic rings, and a couple of moon gels on the beater head

  4. A couple new systems you missed that are very cool are the post-tensioned rocking shear walls that are purposefully designed to rock, but not fall, and the joints of the rocking would be specially designed to not have significant damage post-earthquake, and some quickly-replaceable systems, like steel-sheet shear walls and some pre-manufactured products.

  5. putting this Tech underneath a building makes no sense especially when the entire ground is shaking or moving. it's only logic, there's no way you can stop hundreds or even thousands of miles of ground from moving if unless you can get to the epicenter of that movement and still no technology we have can prevent it

  6. Wood was or is also making a comeback because of that, right? They figured out a way to make wood waaaay more resistant to fires, and then you get the benefit of it being flexible enough to resist earthquakes. Or so I heard.
    It's also interesting to look into japanese architecture… I was watching a doc about the reform they did on Tokyo Station. The entire thing was lifted to sit on top of a moving platform of sorts. The scale is baffling.

  7. I'm surprised the tree resonators/reflectors (can't remember proper term) didn't come up. About a year ago a study into placing trees of increasing lengths near a building was shown to act like a reflector for surface waves. Perhaps no more has been heard :P.

    http://live.iop-pp01.agh.sleek.net/2018/01/25/how-forests-could-limit-quake-damage-to-buildings/

  8. What about lots of iron balls under the building. Basically the building just rolls on top of the balls when there is an earthquake…

  9. What's the upper size limit on the "invisibility cloaks"? How big of an area could they cover? Would it be possible to just create a massive one that protects the whole city, rather than just that one building?

  10. Excellent update on earthquake technology! Thanks, SciShow! (Not a "science" topic is the socioeconomic factors of architecture, where cost is a factor in how well buildings themselves are constructed to limit damage and mortality during an earthquake,…but that's a whole other discussion.) Thanks again for this presentation!

  11. And then put that box in another box. Then I mail that box to myself, AND THEN I SMALL IT WITH A HAMMER!

  12. We got hit by a 6.9 quake here and half of the city was in a really horrible shape..

    Quakes are VERY real and scary. We had more than 10 in the last 15 years. Nothing to joke about for sure

  13. At 5:41 the bridge shown, Queensboro Bridge, is not a suspension bridge.

    It’s a cantilever truss structure.

  14. Everybody just ignoring the easy solution…make your buildings fly. It's 2019 for Pete's sake!

  15. What happened to the enthusiasm. I like my science to be fun and quirky. If I wanted actual boring science I'd read a book. You didn't even include a plug to whatever show you did about how freaking cool mantis shrimp are.

  16. Lighthouses used buttresses to change the building response to earthquakes. Check out the rebuilding of the lighthouses along the san andreas fault.

  17. I've said this before, but the shadows on your face from your glasses make it look like you've got crying tears makeup. The lighting should illuminate your face using a more diffuse manner than a spot as you currently have… even if your spotlights are diffuse.

  18. mechanical engineer here. this video takes me back to vibrations class. when she said "frequencies the building is most vulnerable too" my mind immediately jumped to resonant frequencies

  19. she's way hotter than any of the fake nerds on the big bang theory. i'd like to show her my own big bang theory

  20. Just place an Arianna Grande in every tower so she can swing side to side and counteract earthquakes

  21. Most of these "problems" we have are simple to solve:

    Cold: wear layers and/or move somewhere warmer
    Hot: love the skin you're in and/or move somewhere cooler
    Tornados: Don't live near any!
    Earthquakes/fault lines: See "Tornados"
    Hurricanes: I really like fish, so…good luck!

    Basically, our ancestors had the right idea: a nomad life is best, not to mention healthier than a sedentary one!

  22. Well, all of that is great for horizontal shaking, but in the Christchurch EQ, we had vertical shaking which meant the ground fell out from under the buildings at more than 2 x the speed of gravity. Hopefully they're working on that, too.

  23. I like this method. If you can't predict the weather, make the weather cause less damage to infrastructure.

  24. "Harry's invisibility cloak was significantly less useful than he thought when he realized it only made him invisible to earthquakes."

  25. There are some other kinds of dampers, and also all of the most basic anti-earthquake measures that tend to actually be required by building codes were completely ignored by this video.

  26. In Japan they are making buildings that “float” so the the liquefaction of the ground during an earthquake has no effect. The same technique was used on a medical building in Astoria, Oregon

  27. Why not create comething that forces the seismic waves away? Is that possible? Idk (credit to BH6 the series)

  28. I resisted saying this because overall the video is great. But in reality, Structural engineers provide tuned mass dampers to reduce the wind-induced accelerations in buildings for occupant comforts and not for seismic protections.

    I design high rise buildings in earthquake-prone regions like the US west coast and in no tall building, you will see tuned mass dampers as a seimsic solution. Because buildings respond at different frequencies while tuned mass damper can help a building at one particular frequency, it becomes useless in earthquakes as the response of a building is more often at high frequencies rather than primary frequency that the TMD was tuned to. A much more efficient solution is using viscous dampers.

    Even in TAIPEI 101, the dampers excitation during an earthquake was inconsistent again because of the high-frequency nature of the ground motions. The engineers themselves would not have counted the damper as the source of energy dissipation in seismic excitation.

  29. They should like put a generator on those mass dampers, so they could generate energy from the wind and earthquakes.

  30. This video went from older methods (but not all of them) to stuff that’s way farther out and glazed over pretty briefly. Wish there was more about how we actually earthquake-proof buildings currently. (I’m an architect)

  31. Nice documented video. The real drama is actually at the residential level. Middle East, Asia, there are thousands of large cities and rural districts build on top of known earthquake risk zones. Poorer populations have been building their homes with low quality materials, with no seismic criteria, in countries where governments don't enforce construction norms. Millions of people live in such constructions. China, Japan, Nepal, Turkey, when earthquakes hit, the human drama is touching. Even in Japan, thought to be the safest place, in many large cities thousands of people live in poorly constructed houses (see Kobe earthquake). The drama is really touching, Kobe not only has been razed, the houses also caught in fire from ruptured gas lines. I hope something will be done with houses in poorer countries, perhaps there can be developed homes from prefabricated components respecting earthquake norms, made of materials other than brick and concrete. Some lighter and stronger constructions. We need to innovate because the need is important and earthquakes can decimate large areas.

Leave a Reply

Your email address will not be published. Required fields are marked *