# Earthquake Proof Buildings?   Science Fair Project with Justin

https://www.youtube.com/watch?v=9N8iQ9Ch8nw

[00:00] Ah, it's an earthquake, just kidding.
[00:03] Today I want to show you two ways how to make an earthquake proof building.
[00:09] [Music]
[00:12] Hi, my name is Justin.
[00:15] I've always wondered what the natural disasters are and how people die in them, so I researched about earthquakes.
[00:22] As I researched, I found out that it's not earthquakes that kill people; it's the buildings that collapse on the people when they're inside.
[00:32] So I started to wonder what can I do to help reduce the amount of people that die in an earthquake.
[00:38] So I did a lot of research and I talked to people in different companies and I found two building techniques used by architects and engineers to help a building withstand an earthquake long enough for the people to get out safely.
[00:53] The two building techniques are base isolation and tuned mass damper.
[00:59] So I wanted to.
[01:01] Find out if these techniques actually work and if I could build a model to show how effective they are.
[01:08] To test these properly, I built a shake table.
[01:14] So let's start with the tuned mass damper.
[01:16] We got this idea from Taipei 101 in Taiwan.
[01:21] The tuned mass damper is often used in tall structures.
[01:23] It's a heavy weight that's suspended on the inside of the building to help minimize the movement and vibration.
[01:33] It's time to make my buildings and test it out.
[01:36] I use pieces from my engine construction kit to make two identical structures that are three stories high.
[01:45] I built my tuned mass damper putting 12 washers on the eye bolt and screwing the nut on.
[01:52] I built an extra part on the top of this building so I could suspend the tuned mass damper on it.
[01:59] Now it's time to test it on the shake.
[02:02] Table, see how much of a big difference there is.
[02:08] The building with the tuned mass damper stays pretty steady and doesn't wobble or bend too much.
[02:13] Check out the building without the tuned mass damper; it swang like crazy.
[02:19] This seems to work because when the building sways one direction, the tuned mass damper moves in the opposite direction and pulls it back from swaying too far.
[02:30] Some of the variables that would change the outcome of this experiment is the height of the tuned mass damper.
[02:37] If it's too high, it will not make a difference, and if it's too low, it will swing too much.
[02:43] Also, the height of the building makes a difference.
[02:47] And the weight for the tuned mass damper: if it's too heavy, it might crush the building, and if it's too light, it won't make a difference.
[02:56] So it looks like the tuned mass damper is very effective at minimizing the movement and vibration in a tall building.
[03:03] Building now on to our second building technique, base isolation.
[03:06] Basically, you're taking the building and lifting it off the ground and putting a shock absorber between the ground and the building.
[03:17] It isolates the building so it won't move as much during an earthquake.
[03:23] There are many ways to do this, but we like the straddling pendulum technology by Straddling Pendulum Limited in Alaska.
[03:32] We measured and cut our test unit out of cardboard.
[03:35] This was tricky because we had to be as exact as possible in our cutting so it fit together well.
[03:43] That helped me out by using an X-Acto knife to cut with.
[03:47] Once it was assembled, we put it on our shake table with heavy books on top to simulate the weight of the building.
[03:55] We put another test building beside it, but with the base sitting directly on the shake table.
[04:02] We put a container of water on top of.
[04:05] Each so we could see what the difference was between our buildings.
[04:10] Look at the difference between them.
[04:12] We found that when we moved the shake table slowly it didn't make much of a difference.
[04:16] But when we shook it quickly it made a huge difference.
[04:20] This worked because the swinging plates absorb the energy from the shake table so it minimizes the movement to the building.
[04:30] One of the variables that would change this experiment's outcome is the height of the legs of the base isolation unit.
[04:39] In fact we made a shorter base isolation unit and it wasn't nearly as effective as the taller one.
[04:44] The other thing that made a difference was how accurately you cut your materials, what it's made of, and the weight of the building on top.
[04:54] So base isolation is a good technique to use when you're trying to make an earthquake resistant building.
[05:04] Based on our two experiments I can say.
[05:07] That, yes, it is possible to make a building that will withstand an earthquake using either base isolation or tuned mass damper.
[05:14] I think tuned mass damper is best for skyscrapers and tall buildings, and base isolation is better for houses and banks and other buildings that are lower.
[05:24] A special thanks to Larry Bullis at Straddling Pendulum Limited.
[05:27] He gave us tips and lots of advice about how to make the base isolation unit.
[05:36] It's great to know that there's technology like base isolation and tuned mass damper that can save people's lives when an earthquake hits.
[05:46] I hope you learned as much as I learned from this.
[05:49] Thanks for watching our video.
[05:51] Bye.
[05:55] [Music]