JAPAN QUAKE: Pitt Experts Available to Discuss Quake’s Unusual Strength and Duration, Resilience of Japan’s Infrastructure to Earthquake and Tsunami, and Integrity of Nuclear Plants

• Pitt seismologist Bill Harbert says University of Pittsburgh seismograph detected the 8.9-magnitude quake for 3 hours, a rare magnitude and strength
• Pitt structural engineer Kent Harries says that much of Japan’s infrastructure is among the most disaster-resistant in the world, but preparing structures for earthquakes versus tsunamis requires opposite building principles
•  Pitt nuclear engineer John Metzger says that the lessons learned from Three Mile Island in 1979 mean Japanese reactors are stable as long as cooling mechanisms remain intact and, should they fail, would allow lengthy response time

PITTSBURGH—The 8.9-magnitude earthquake that shook Japan March 11 was not only unusually strong, but also strained Japan’s earthquake-resistant civil and nuclear power infrastructure, a seismologist, a structural engineer, and a nuclear engineer from the University of Pittsburgh said.

 Bill Harbert, Pitt seismologist and professor and geophysics professor, is available to discuss seismic details of the Japan quake and analyze it in context to other quakes. He says the Japan quake was remarkable for its magnitude and duration as recorded at Pitt's seismic station—about three hours. Harbert oversees Pitt’s seismic station, which detected the quake at approximately 5:46 a.m. GMT and registered near-constant activity until close to 9 a.m. GMT.

Images from Pitt’s seismograph are below. The first image displays the hour (GMT) on the left margin and the minutes on the bottom line. The earthquake is represented by the jagged lines that begin at the 40 minute mark of line 05 and continue to the end of line 8. The second image displays the earthquake’s vertical displacement of the ground (the units to the left do not correspond to any particular unit of measurement) with the duration indicated in minutes since 5 a.m. GMT.

Kent Harries, a structural engineer and professor of Civil and Environmental Engineering in Pitt’s Swanson School of Engineering, said that much of Japan’s infrastructure is among the most disaster-resistant in the world. Still, earthquake- and tsunami-resistant construction calls for entirely different principles: for tsunamis, buildings need to be able to let water pass through (such as beach houses on stilts),while structures need a solid base to withstand an earthquake. Although Japan has done well incorporating both designs, Harries said, “the tsunami clearly seems to be the dominant source of destruction.”

John Metzger, a nuclear engineer and associate professor of mechanical engineering and material science in Pitt’s Swanson School of Engineering, said that emergency procedures, modern reactor and plant designs, and lessons learned Pennsylvania’s Three Mile Island incident in 1979 mean that Japanese reactors will likely remain stable. Although Japanese plants are releasing gasses as a precaution, the reactors’ crucial stop-gaps are intact, Metzger said. Reports indicate that there has been no loss of reactor coolant, that emergency power has been reestablished, and that heat-removal systems are functional. Most importantly, it seems no reactor cores were damaged, he said. Modern reactors permit a lengthy amount of time to respond and it appears that Japanese engineers were able to re-establish core cooling in a reasonable amount of time, Metzger said.

Contact Bill Harbert, Kent Harries, or John Metzger through Pitt News Representative Morgan Kelly at 412-624-4356 (office), 412-897-1400 (cell), mekelly@pitt.edu.

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