Tire-Soil Mixture Buffers From Quakes. Linda Blake

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The Earthquake Cushion—a finalist in the Asian Innovation Awards—is made of soil and tire chips that form a layer below and around a building's foundation and reduce earthquake shaking by 50% on average, according to the university's in-house computer simulations.

"This is a paradigm shift," said Dr. Tsang, since there is no other earthquake protection technology that operates in this way. The cushion dissipates seismic energy before the waves reach a building's foundation. This differs from the traditional earthquake proofing—like laminated rubber bearings—which are installed between a building and its foundation. As a result, the bearings are a part of the structure and seismic waves can still potentially damage a building before they are dissipated, explained Dr. Tsang.

In the past decade, an average of 60,000 people a year have died from earthquakes. The vast majority was in impoverished countries, the journal Nature reported recently. The 2010 earthquake in Haiti leveled more than 100,000 buildings. The majority of the roughly 300,000 people killed were crushed under the rubble.

For example, a three-story building that's 10 meters wide costs roughly $63,000 to build in mainland China. The Earthquake Cushion would cost about an additional $3,100. "This small cost would go toward excavation, deposition and compaction of the rubber-soil mixture," Dr. Tsang said. To install laminated rubber bearings—a more common earthquake-protection method in developed countries—would typically cost 10% of the total construction cost, Dr. Tsang said.

The earthquake cushion is still going through preliminary tests to gauge its effectiveness and safety before it is used on buildings. To date, the university has run computer simulations that track the cushion's performance against actual earthquake models, including the 7.8-magnitude earthquake that struck Chile in 1985. Researchers varied the number of building stories and width of the cushion. In all cases the cushion effectively reduced both horizontal and vertical ground motion by 40%-60%.