12:39 p.m., July 10, 2009----Greg Black, a master's candidate in civil engineering at the University of Delaware, has spent the past two years studying seismic effects on woodframe buildings via computer models. On July 14, he will witness what is almost the real thing when a seven-story, 40- by 60-foot condominium building weighing almost a million pounds will be tested at the Hyogo Earthquake Engineering Research Center in Miki City, Japan.

THIS STORY

E-mail

Print

Twitter

The research center's “shake table,” which measures approximately 65 by 49 feet and can support building experiments weighing up to 2.5 million pounds, is being used to recreate a series of earthquakes, including a 2,500-year earthquake, considered to be the maximum credible earthquake (MCE) in Los Angeles.

The test, which will make history as the largest shake table test to date, is being conducted under the National Science Foundation's Network for Earthquake Engineering Simulation NEESWood project.

NSF will Webcast the event at 11 a.m., Tuesday, July 14, and, while there currently is a password requirement on the Webcast site, that will be lifted the morning of the test so the public can watch.

Led by Colorado State University, NEESWood also includes researchers from Texas A&M University, Rensselaer Polytechnic Institute, and the University at Buffalo. The project focuses on development of a performance-based seismic design (PBSD) philosophy for woodframe buildings. PBSD differs from past design practice, in which buildings were designed only to codes guaranteeing life safety, by enabling incorporation of performance factors that will limit economic losses.

Black's faculty adviser, Rachel Davidson, associate professor in the UD Department of Civil and Environmental Engineering, is a member of the NEESWood team.

Davidson's role in NEESWood is to address societal risk. Her work has two main thrusts, one focusing on how losses vary with the stated performance objectives for a particular building, the other on how the distribution of regional losses would be affected by adoption of PBSD through various implementation scenarios. “For example, we could implement the design philosophy for all new buildings, or we could target certain building types or geographical areas,” Davidson says.

Black's research focuses on development of a loss model for woodframe buildings subject to seismic events. The model uses dynamic response and fragility data for various building components such as shear walls. Black is applying the model to a set of buildings designed using both PBSD and traditional design procedures to obtain loss data for a range of ground motions for each design. His goal is to quantify the potential benefits of using the new philosophy over the old one for each building type and to help inform the specification of performance objectives in the new PBSD method.

The test in Japan will provide him with data that will allow him to assess the accuracy of his model and calibrate it appropriately. He will be able to compare the actual dynamic response of the structure to its predicted response and the actual damage to the results of his fragility analysis.

But, more importantly, the trip will enable him to meet with the other members of the project team as well as with the top Japanese structural and earthquake engineers. “This will be a great opportunity for me to be part of discussions about the implementation of the test and to observe the results firsthand,” Black says.

“The test is the NEESWood project's capstone test,” says Davidson, “and it will provide us with extensive information about the dynamic response of woodframe structures to seismic events. I'm really pleased that Greg will have the opportunity to participate in it.”

Article by Diane Kukich