STANFORD (KPIX 5) — Stanford engineers have developed an earthquake-proof home they say can withstand an quake three times more powerful than the October 17, 1989 Loma Prieta earthquake.
“If it starts to get to that level that would trigger damage in your house, the house would simply slide and the house remains damage-free,” said Stanford professor Eduardo Miranda.
Miranda and his team developed two techniques that would keep homes intact during the Big One.
One design frees a home from the foundation. Instead of bolting the home down, sliders that sit in steel bowls are used on the foundation.
The sliding can be up to 15 inches. “It’s not like you’re going to be 15 inches closer to your neighbor. But actually it returns back to essentially the same point where it was.”
Miranda says the second design improvement came from the auto industry – uni-body construction.
For a home, that means using glue, additional screws and extra-thick sheetrock for the interior walls. Mesh and screws on the outside before stucco is put on.
Both techniques are primarily for new construction. Retrofitting would be expensive, said Miranda.
But, considering San Francisco is now notifying owners of so-called “soft story” buildings that they must make quake safety improvements, Miranda says the new techniques would be worth it.
“The city of San Francisco wants to avoid having thousands of people who don’t have a place to live after an earthquake because it’s a tremendous economic loss to the community, to the city as a whole,” he said.
For new construction, Miranda estimates the sliders and uni-body designs would add about $10-thousand dollars to each home, which could be more than be made up for in insurance and repair costs.