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Could Buildings "Hover" Above an Earthquake?

Posted August 08, 2015 12:00 AM by Engineering360 eNewsletter

The creator of the hoverboard has proposed a three-part foundation that, he claims, could prevent buildings from shaking during an earthquake. The patented idea combines the U.S. Geological Survey's ShakeAlert system with a magnetic-field architecture. When the foundation senses an event it goes into "hover mode," essentially decoupling from the event. The inventor says the system could be retrofitted to existing structures, but is better suited to new construction.


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#1

Re: Could Buildings "Hover" Above an Earthquake?

08/08/2015 4:14 AM

I'd suggest the amount of isolation provided could be achieved by simpler, less expensive and more reliable means.

Del

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#2

Re: Could Buildings "Hover" Above an Earthquake?

08/08/2015 7:49 AM

Buildings are really heavy. There is no way to levitate one with a magnetic field.

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#3

Re: Could Buildings "Hover" Above an Earthquake?

08/08/2015 8:39 AM

If it shakes enough, but only for a moment, then all hell breaks loose.

Seriously. Even a small house's mass is 70,000 kg with the foundation, g = 9.8 m/s^2, so the force in Newtons to do this is F = ma = 70,000 kg • 9.8 m/s^2 = 6.86 • 10^5 N.

That's 686 kW assuming the energy is converted at 100% efficiency. That's just one house.

This in the land where turning your AC on in the summer is likely to take down the grid?

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#4
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Re: Could Buildings "Hover" Above an Earthquake?

08/08/2015 9:27 PM

I'm not sure how you got from Newtons to KW, but I agree with you, anything that requires a lot of energy is a non starter.

I can see decoupling a structure from the ground by having a foundation consisting of parallel rollers (say north-south) on top of a perpendicular series of rollers (east-west). The rollers would be constructed of a material strong enough to support the building weight. When the ground shifts, the mass of the building would more or less hold it in place.

I don't know if this is feasible, just an idea being thrown out.

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#5
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Re: Could Buildings "Hover" Above an Earthquake?

08/08/2015 10:56 PM

...or big ball bearings...

...or these things....

The problem is it costs too much to be widely used....

http://sfcityguides.org/public_guidelines.html?article=1592&submitted=TRUE&srch_text=&submitted2=&topic=

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#6
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Re: Could Buildings "Hover" Above an Earthquake?

08/08/2015 11:26 PM

Simple. 1 Watt = 1 Newton meter/sec

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#10
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Re: Could Buildings "Hover" Above an Earthquake?

08/09/2015 7:48 AM

Where does 1 meter/sec come from?

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#11
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Re: Could Buildings "Hover" Above an Earthquake?

08/09/2015 10:15 AM

Force (in Newtons) times velocity. One Newton m/s = 1 Watt.

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#8
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Re: Could Buildings "Hover" Above an Earthquake?

08/09/2015 2:42 AM

Yeah but when you get home drunk and lean on the front door trying to get the key in the lock....

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#7

Re: Could Buildings "Hover" Above an Earthquake?

08/09/2015 1:03 AM

create lake type foundation for each building to float like a boat.

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Re: Could Buildings "Hover" Above an Earthquake?

08/09/2015 3:23 AM

Get a naval architect to design it.

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#12
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Re: Could Buildings "Hover" Above an Earthquake?

08/09/2015 1:26 PM

Then we would have to worry about Tsunami....

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#13
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Re: Could Buildings "Hover" Above an Earthquake?

08/09/2015 6:13 PM

The structural engineers at CR4 said the building was not strong enough to add a third floor and suggested we would be better off spending our money on a boat. So we did and it worked out great!

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#14
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Re: Could Buildings "Hover" Above an Earthquake?

08/09/2015 6:59 PM

we'er just going to have to wait for the next high tide, little buddy.

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#15
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Re: Could Buildings "Hover" Above an Earthquake?

08/09/2015 8:16 PM

Tsunami won't affect indoor pools if located far from beach.During earth quake not only buildings shake but falling debris and trees too can cause damage.

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Re: Could Buildings "Hover" Above an Earthquake?

08/09/2015 10:27 PM

Pool tsunami....

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#17
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Re: Could Buildings "Hover" Above an Earthquake?

08/10/2015 4:11 PM

Watch this, hold my beer! -- JHF

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#19
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Re: Could Buildings "Hover" Above an Earthquake?

08/11/2015 12:06 AM

Penthouse apt for rent....nautical theme

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#18

Re: Could Buildings "Hover" Above an Earthquake?

08/10/2015 10:08 PM

My question is this, if you levitate the building during a quake what happens when the previously solid foundation is destroyed during the event? where are you going to put the building down when it's over?

Seems to me if this happens then the building is a goner or am I missing something?

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#20
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Re: Could Buildings "Hover" Above an Earthquake?

08/11/2015 7:32 AM

No system is designed to accomplish the impossible. Like existing systems for buildings and structures in earth quake prone areas it is designed to mitigate the problem as much as possible within the limits of technology and budgets.

This proposal is another way to skin the cat (sorry Dell), but I question the energy budget required to do this as something that is practical.

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