MCEER/NCEER Bulletin Articles: Workshop/Conference Reviews...
Third U.S.-Japan Workshop on Earthquake Protective Systems for Bridges
The Third U.S.-Japan Workshop on Earthquake Protective Systems for Bridges was held in Berkeley, California on January 24 and 25, 1994. The workshop was organized by NCEER in cooperation with the Public Works Research Institute of the Ministry of Construction, Japan, and held under the auspices of Task Committees G and J of the UJNR Panel on Wind and Seismic Effects. The workshop was attended by 45 U.S. and 32 Japanese participants. In addition, one participant each from New Zealand and Canada, and two from Taiwan, attended.
The workshop addressed current developments in both the United States and Japan, and explored the potential for future cooperation in the design and application of systems for the protection of bridges from earthquake effects. The workshop consisted of presentations and discussions of 14 U.S. and 18 Japanese papers with a focus on research and the application of technology, rather than state-of-the-art reviews. The papers covered a wide range of topics including seismic isolation hardware, testing of isolated bridges and components, active control and hybrid systems, design issues and applications, long span bridges, seismic retrofitting, and new construction.
Of continuing interest is the difference in philosophy between "menshin" design in Japan and seismic isolation as practiced in the United States. Participants also showed great interest in hybrid and active systems for bridges, as well as special applications of passive systems; e.g., the design of very long bridges on soft soils.
The workshop was held the week following the January 17, 1994, Northridge earthquake. Many of the workshop participants were concerned with the impact of the earthquake on the region in and around the city of Los Angeles including, but not limited to, the performance of various seismically-isolated buildings and bridges. This earthquake, along with the Loma Prieta earthquake of 1989 and the Kushiro-oki and Hokaido Nansei-oki earthquakes of 1993, demonstrated the fragility of existing urban infrastructure and its importance to public commerce and regional economies. The participants recognized these issues and agreed that further research efforts should be directed towards the development of new intelligent systems and protective measures. It was agreed that the future emphasis should be placed on a systems approach to studying the transportation infrastructure and should included consideration of not only safety, but also performance, maintenance, and operational efficiency.
A study tour of seismically isolated bridges in the San Francisco Bay area was undertaken by the participants on Saturday and Sunday, January 22 and 23. This tour was performed jointly with participants from the Second U.S.-Japan Workshop on Seismic Retrofit of Bridges, which was organized by the University of California at Berkeley and was held on January 20 and 21, 1994, at the same location. A number of the Japanese participants also visited areas damaged by the Northridge earthquake both prior to and immediately after the Protective Systems workshop. The program coordinators for the workshop were Dr. Ian G. Buckle, professor of civil engineering at the State University of New York at Buffalo, and Dr. Kazuhiko Kawashima, Head of the Earthquake Engineering Division of the Public Works Research Institute. A Steering Committee consisting of Ian G. Buckle, Masanobu Shinozuka, Stephen A. Mahin, and Ian M. Freidland arranged the workshop on behalf of the participants.
Organizational support for the workshop was provided on the Japan side by the Public Works Research Institute. U.S. financial support was provided by the National Science Foundation, the National Institute of Standards and Technology, and the Federal Highway Administration of the U.S. Department of Transportation.
NCEER Bulletin, Vol. 8, No. 2, April 1994