Architecture

Stanford researchers develop earthquake-resistant house prototype

Stanford researchers develop e...
The significance of the Stanford research lies in its inexpensiveness and ease of installation (Photo: Stanford School of Engineering)
The significance of the Stanford research lies in its inexpensiveness and ease of installation (Photo: Stanford School of Engineering)
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The prototype model home was tested on an earthquake simulator (Photo: Stanford School of Engineering)
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The prototype model home was tested on an earthquake simulator (Photo: Stanford School of Engineering)
Thanks to the seismic isolators, the house slid harmlessly from left to right during tests (Photo: Stanford School of Engineering)
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Thanks to the seismic isolators, the house slid harmlessly from left to right during tests (Photo: Stanford School of Engineering)
The significance of the Stanford research lies in its inexpensiveness and ease of installation (Photo: Stanford School of Engineering)
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The significance of the Stanford research lies in its inexpensiveness and ease of installation (Photo: Stanford School of Engineering)
The significance of the Stanford research lies in its inexpensiveness and ease of installation (Photo: Stanford School of Engineering)
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The significance of the Stanford research lies in its inexpensiveness and ease of installation (Photo: Stanford School of Engineering)
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Though a large earthquake can prove catastrophic to life and property, even relatively minor tremors may compromise the structural integrity of a home, resulting in large repair costs. A team of engineers based at California's Stanford University has developed a new method of building earthquake-resistant homes that could be implemented relatively easily and inexpensively.

The Stanford engineers built a small two-story home model that features what they refer to as a "unibody" design. Rather than screwing drywall to the home's wooden frame, it was attached with glue, while strong mesh and additional screws were used to attach and keep the white stucco facade safely in place.

More significantly however, the home was not placed on a standard foundation, but on "seismic isolators." The seismic isolators comprise 12 steel-and-plastic sliders, each measuring around 11.4 cm (4.5 in) in diameter, and plates and bowl-shaped dishes made of galvanized steel were placed beneath.

Thanks to the seismic isolators, the house slid harmlessly from left to right during tests (Photo: Stanford School of Engineering)
Thanks to the seismic isolators, the house slid harmlessly from left to right during tests (Photo: Stanford School of Engineering)

The prototype model home was tested on an earthquake simulator that essentially acts as a large shaking table. Though unable to give a Richter scale reading, the engineers report that they shook the table at three times the intensity of a 6.9 magnitude quake. Thanks to the seismic isolators, the house slid harmlessly from left to right, but took no damage. Indeed, it wasn't until the researchers turned up the earthquake simulator up to maximum that the building displayed significant damage.

Of course, the principle of seismic isolators isn't new, and they are already used to protect some larger structures, like San Francisco International Airport for example. However, the significance of the Stanford research lies in its inexpensiveness and ease of installation. The researchers report that their system would only add around US$15,000 to the total cost of a typical 185 sq m (2,000 sq ft) full-sized house.

Though retrofitting the earthquake-resistant technology to an existing home is possible, the researchers say that a new build would be much easier and only take contractors roughly four additional days to install.

The video below shows the model home being tested.

Source: Stanford News

Stanford engineers build an earthquake-resistant house

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5 comments
michael_dowling
What utter BS. SIP constructed houses are earthquake proof,termite proof,super insulated,go up fast in a matter of days.They have withstood tornadoes while houses around them have been destroyed.A test house put on a earthquake simulating "shake table" broke the table,and the house was fine.
Stephen N Russell
Now build some & test in quake zones worldwide.
Slowburn
And how strong of a wind does it take to sweep you off the seismic isolators?
Bob
It was tested to three times the force of a 6.9 earthquake which is what? 7.2 ? I noticed that all the movement was two dimensional rather than three dimensions like a real earthquake would be. There was nothing to keep the small pads from sliding off the base(other than the slight bowl shape) if several shocks were in the same direction. And finally, there was nothing to recenter the house on the pads after it was over. While wire mesh in the stucco no doubt helps, it should also be over the inside dry wall. What about flexible utility pipe joints between the house and foundation. On a small frame house I would be more worried about fire than collapse. Why not try a steel framed house that could withstand a little more flexing or wall board with imbedded fibers? I suspect that this house would still experience much more damage than the article leads us to believe. How do you re-glue all that wallboard without removing it?
muchado
"Though unable to give a Richter scale reading, the engineers report that they shook the table at three times the intensity of a 6.9 magnitude quake."
Just in case anyone is wondering, this doesn't mean that the engineers don't know what they are doing, but rather that it doesn't make sense to talk about the Richter scale in this context, so the author is demonstrating a lack of understanding. It is like asking whether you could be blinded by the light from the star Sirius. Not on earth under normal circumstances, but if you got close enough you would...
A 6.9 quake at a certain location and depth would produce varying levels of ground shaking at the surface, which would also depend on the path for the motions. The frequency content would also vary by location and by the nature of the fault rupture.
The Richter scale is related to the amount of energy reduced, but does not tell you what the effect at the surface will be, and therefore the result on the buildings on the surface. It would be better to talk in terms of local ground acceleration or in terms of intensity (e.g. Modified Mercalli Index). So... the person who says, "That felt like 5", probably doesn't know what they are talking about.