Today, Bastille Day, a six-story condominium building was shaken with same type of the motions of the 1994 Northridge earthquake, but one and a half times as intense--more powerful than any quake California has experienced in modern times.
The capstone experiment of NSF's multi-year NEESWood (it was harder than it should be to find out that stands for Network for Earthquake Engineering Simulation Wood) project, the effort will test new ways to construct buildings that can withstand severe forces of nature.
Working with the Japanese government's National Research Institute for Earth Science and Disaster Prevention (NIED), as part of a broader partnership with NSF, the NEESWood engineers tested their structure at the E-Defense facility, located north of Kobe, which houses the world's largest shake table.
On June 30th, the entire, sensor-laden structure was subjected to two tests, one simulating earthquake forces that occur, on average, once every 72 years and a second that would occur similarly once every 475 years. On July 6th, the same tests were run, but the steel-frame components were locked down, so only the six-story, wood-frame, residential structure would be affected.
Today the wood-frame structure became the subject of the largest shake table test the world has seen to date, at a level that equates to an event that occurs, on average, once every 2,500 years.
See photos and movies at NSF.