Prof. Keri Ryan – 3-Dimensional Shake Table Testing of a Full-Scale Seismically-Isolated Building

Abstract:

Through a Memorandum of Understanding between the U.S. Network for Earthquake Engineering Simulation (NEES) and Japan’s National Institute of Earth Science and Disaster Prevention, a full-scale shaking table test of a 5-story base-isolated was carried out at Japan’s Hyogo Earthquake Engineering Research Center (E-Defense) in 2011. The building was tested with two different isolation systems (triple pendulum bearings and a hybrid system of lead-rubber bearings and low-friction rolling cross-linear bearings) and in the fixed-base configuration. The tested building had a realistic floor system, nonstructural components (suspended ceilings, sprinkler piping and interior walls), and furnishings, and was subjected to strong earthquake shaking. The tests served as a full-scale proof of the concept of seismic isolation to protect the building from damage in very strong earthquake shaking; for instance, displacement demands across the isolation system were more than twice what has been observed in any previous earthquake event. However, the nonstructural components and furnishings were not completely protected from damage, and the tests showed that these items were sensitive to the vertical component of ground shaking, which is unaffected by the seismic isolation system. While the overall performance of the isolation systems was very impressive when considered against other available options for seismic protection, the tests highlight the challenge of designing a building to remain immediately operational following a large earthquake. This presentation will summarize the test program, present the major findings, and discuss future directions in research, design practice, and seismic isolation building codes.

Biography

Keri Ryan is an Associate Professor of Civil Engineering and a member of the Center for Civil Engineering Earthquake Research at the University of Nevada, Reno. She specializes in earthquake engineering and protective systems for high seismic performance, with application to buildings and bridges. She was the PI of the U.S. National Science Foundation funded “Tools for Isolation and Protective Systems” (or TIPS) project to address impediments to the wider application of seismic isolation systems, and she led an international collaborative test program between the U.S. and Japan that conducted earthquake testing of a full scale building comparing conventional and alternative construction approaches. Ongoing research examines ways to ensure that high seismic performance objectives can be met. She has authored more than 50 publications on topics related to seismic isolation, high seismic performance, and life cycle analysis of structures.