EAPSI: Evaluation and Comparison of the Collapse Vulnerability to Earthquakes of Steel Frame Buildings in the U.S. and Japan

Buyco John K, Pasadena CA

Investigators

Abstract

This research will be conducted at Kyoto University in Japan under the supervision of Dr. Masayoshi Nakashima, professor (and former director) at the Disaster Prevention Research Institute of Japan and a leader in U.S./Japan joint research programs in earthquake engineering since the 1980s. The project will investigate the vulnerability to earthquake-induced collapse of steel frame buildings in Japan. Representative 6-story steel frame buildings that incorporate Japanese design codes and common design practices will be designed and corresponding computer models will be simulated by the researcher. The researcher has completed a similar project with 6-story buildings designed based on U.S. building codes and design practices, so comparisons will be made between buildings from both countries. This research project will demonstrate the relative earthquake safety of buildings in the U.S. and Japan and is part of a larger effort to help communities better understand the risk for collapse of their buildings. The project will provide a framework to estimate the collapse vulnerability of 6-story steel moment frame buildings in Japan. The researcher?s past work has developed a framework for estimating the ultimate strength and ductility of 6-story steel moment frame buildings in Los Angeles based solely on the construction year and location within the city. The project will extend this work to Japanese buildings. Representative buildings will be designed based on the main seismic zones and soil types in Japan according to design codes and practices before and after 2000 (a year of major changes in the seismic code of Japan). Pushover analysis will be conducted to determine the ultimate strength and ductility of these buildings. A relationship will be developed between these two parameters and the design base shear and/or construction year. As this framework develops, it will allow researchers to computationally efficiently conduct large scale simulations on the city-wide scale to scenario earthquakes in order to accurately determine the city?s earthquake resiliency. Comparisons will be made to U.S. buildings to see how the different design codes and engineering practices affect building performance with regards to collapse. This award under the East Asia and Pacific Summer Institutes program supports summer research by a U.S. graduate student and is jointly funded by NSF and the Japan Society for the Promotion of Science.