OREGON STATE UNIVERSITY

EARTHQUAKE SIMULATION TO PROVIDE SNEAK PREVIEW OF "BIG ONE"

01/28/2004

CORVALLIS - The great subduction zone earthquake feared by many residents of the Pacific Northwest will hit one part of Oregon tonight at 7 p.m.

Fortunately, it's just a very small part, a wood frame wall about eight feet square. And no, the science of earthquake prediction has not taken a quantum leap forward - the shaking and breaking, in this case, will be confined to a lab at Oregon State University and produced by sophisticated equipment.

But the loads and motion forces involved, researchers say, will closely resemble those that a wall of this type - similar to those found in millions of wood frame homes and other structures around the region - would actually face during the "Big One" that researchers believe is looming in Oregon's future.

"This will give us a realistic demonstration of what a wood frame wall will experience during a major earthquake, in this case lasting more than one minute," said Rakesh Gupta, an associate professor in the OSU Department of Wood Science and Engineering. "We'll expect to see plywood crack, nails pop loose and the wall could collapse."

About 50-60 structural engineers, mostly form the Portland area, are planning to be on hand for the demonstration, Gupta said. The event will also be repeated next Monday, Feb. 2, for a class of about 100 students at the university, so that it can serve both a research and educational function.

Wood buildings generally perform quite well during earthquakes, Gupta said, but OSU researchers are exploring ways to build wood frame structures so they are even better at resisting the forces of earthquakes and other natural hazards.

Oregon was once believed to face comparatively little risk from major earthquakes, but researchers now believe that many areas of the state are seismically active, and the entire Pacific Northwest from Northern California to British Columbia faces a significant risk from movement in the subduction zone, where the oceanic and continental plates collide. This type of earthquake would be very infrequent - some evidence indicates the last such event happened in 1700 - but could have catastrophic effects when it occurs every 400 to 600 years.