Preface
E-Defense is the world largest shake table in Miki, Japan constructed by the National Research Institute for Earth Science and Disaster Prevention (NIED). The table is 20 m long and 15 wide with the maximum model load of 1,200 tf. Peak acceleration, velocity and displacement which can be excited by E-Defense under full load are 0.9 g, 2 m/s, +/- 1 m in the two lateral directions, respectively, and 1.5 g, 0.7 m/s and +/- 0.5 m in the vertical direction, respectively.
It was built as a consequence of the extensive damage of urban infrastructures in the 1995 Kobe, Japan earthquake to advance the scientific knowledge in earthquake engineering. It was recognized crucial after the Kobe earthquake to eliminate the existing barriers that prevented realistic shake table tests on the seismic performance of structures to failure due to insufficient table size and model weight. gWhy did structures suffer such extensive damage in the Kobe earthquake?,h gwhat are the mechanism of failure?,h and gwhat extend do structures fail under near-field ground motions?h are the basic motivations of constriction of E-Defense.
A large scale shake table test on bridge structures was identified as one of the high priority research areas using E-Defense. The large scale bridge test project as well as other two research projects (steel buildings and information technology) was initiated in 2005 as a US-Japan cooperative research based on NEES and E-Defense collaboration. The project is being coordinated based on the agreement of Japanese and US researchers at the joint technical coordinating committee, planning meetings, workshops, and program meetings.
Since E-Defense was built for clarifying the extensive damage of structures in the 1995 Kobe earthquake, breakthrough tests using full/large-scale models which are significantly important as a benchmark test for clarifying the failure mechanism and/or enhancing the seismic performance of structures are expected.
As a part of the US-Japan Cooperative Research on Bridges, University of California, Berkeley, Tokyo Institute of Technology and Kyoto University are conducting Joint Research on the Seismic Performance of Bridges in 2006. In this research project, TITech and UCB are focusing on the seismic performance of interlocking spiral columns and rectangular columns. Four specimens were built in TITech and they are excited at UCB using the shake table at the Earthquake Engineering Research Center, UCB. Project PIs are Professor Stephen Mahin, UCB and Kazuhiko Kawashima, TITech. This project is supported by NIED in Japan-side and Caltrans in US-side.
We appreciate the professors and all the staff who support us.
