The E-Defense earthquake simulator prepares to give a good shaking to a six-story building.

The E-Defense simulator, with a 300-sq.-meter "shaking table" powered by 24 pistons, can jolt buildings up to 12,000 tons, according to the National Research Institute for Earth Science and Disaster Prevention, or NIED.

In the experiment, the mammoth device jolted a 16-meter, six-story condominium at velocities similar to those in the 7.2-magnitude quake that hit Kobe in 1995. That quake caused widespread structural damage and killed more than 6,400 people.

The condo shuddered violently in the three-dimensional shaking, its ground floor pillars crumbling to reveal steel reinforcements that had become twisted.

But the structure -- built with methods from the 1970s to reflect many of the country's condos -- stopped short of collapsing in the 40-second experiment, carried out in the city of Miki, just outside Kobe.

Quake simulations involving life-size structures help engineers assess structural damage in ways that aren't possible with models, the NIED said.

Researchers hope the ¥45 billion E-Defense project will be helpful in improving quake-resistant engineering methods.

The NIED plans to conduct similar experiments on various building types, it said.

The Japan Times Weekly: Jan. 21, 2006
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