by George
C. Lee
Multidisciplinary Center for Earthquake Engineering Research
University at Buffalo, State University of New York
On September 21, 1999, at 1:47 a.m. local time
(17:47 p.m. Sept. 20, UT), an earthquake of magnitude ML = 7.3 and Mw = 7.7 took place in
the central part of Taiwan. The epicenter was located at 120.82°E and 23.85°N near the
town of Chi-Chi, Nautou County. The focal depth was 8.0 km. A surface rupture along the
Chelungpu fault of about 105 km was observed, with the largest measured vertical offset
reaching more than 9 meters. After the major shock, 10,252 aftershocks were identified
(till October 10, 1999); four were greater than magnitude 6.5. As a direct result of this
earthquake, over 2,400 lives were lost, more than 10,000 people were injured, over 10,000
buildings/homes collapsed and more than 7,000 suffered damage. This was Taiwan’s
worst disaster since the Shin-Chu Taichung earthquake of April 1935, where 3,325 lives
were lost in a magnitude 7.1 earthquake (Loh and Tsay, forthcoming).
The Multidisciplinary Center for Earthquake
Engineering Research (MCEER) and the National Center for Research on Earthquake
Engineering (NCREE) have enjoyed a long history of research collaboration, beginning in
1992, to investigate earthquake engineering issues of mutual interest. Over the years,
many collaborative projects have been initiated, most notably in subject areas such as
structural control, and evaluation and retrofit of lifelines, especially electric and
power. Shortly after the earthquake struck Taiwan, the two Centers decided to use their
collective knowledge and expertise to identify important short-term strategies/actions for
post-earthquake restoration and research needs. A workshop was convened by Professor C-H.
Loh, Director of NCREE, in Taiwan on October 3-5, 1999 to share information already
collected, and identify teams for further reconnaissance. MCEER and NCREE researchers were
paired together to focus on specific areas. The areas and participants were:
Ground Motion Characteristics - C.H. Loh and
George C. Lee
Geotechnical Aspects - Thomas O’Rourke
and M-L. Lin
Damage to Critical Facilities - T.T. Soong and
G. Yao
Building Damage - Michel Bruneau and K.C. Tsai
Bridge Damage - Ian G. Buckle, K.C. Chang and
J-S. Hwang
Lifeline Damage: Electric Power Systems - M.
Shinozuka and G.Y. Liu
Application of Remote Sensing - M. Shinozuka,
George C. Lee and A.J. Chen
Economic Consequences - Stephanie E. Chang
Emergency Response and Short-term Restoration
- Paul J. Flores
The chapters that follow in this report reflect
the initial observations of the joint NCREE-MCEER teams, and focus on areas of current and
future research collaboration. Many other preliminary reconnaissance reports have been
written (see Selected Bibliography), and MCEER is making an effort to avoid duplication of
efforts by focusing on developing and applying advanced technologies for seismic hazard
mitigation. Future research, based upon the lessons learned and observations made in
specific areas, such as critical facilities and lifelines, structural control, application
of advanced technologies, and emergency response and preparedness, will focus on the
reconstruction of a more earthquake-resilient Taiwan.
In this spirit, MCEER and NCREE met again in
April 2000, together with representatives from the Pacific Earthquake Engineering Research
(PEER) Center and the Office of National Science and Technology Program for Hazard
Mitigation in Taiwan to discuss how to best utilize the extensive data and results
collected by these reconnaissance efforts. Two major areas of emphasis were identified:
the analysis of new information to enhance model validation; and code improvements and
implementation specific to Taiwan.
With these broad areas of emphasis in mind, the
intent of the research program is to apply new reconnaissance information to projects
already in progress at the four Centers. Proposed focus areas include the following:
Ground motion attenuation, site effects,
spatial variation and validation.
Development of retrofit strategies for
buildings shown to be vulnerable by the Chi-Chi earthquake. This includes two parts:
development of specific retrofit ideas for 1-3 story and 8-12 story buildings; and
development of evaluation and retrofit strategies for hospitals and selected manufacturing
facilities including contents.
Development of evaluation and retrofit
strategies, and system analysis for electric power and water systems.
Development of a new system-related loss
estimation methods for HAZ-Taiwan.
Investigation of social and economic issues.
Representatives of the four Centers are planning
to meet, together with other researchers, this fall in Taiwan to discuss the specific
details of the research program.
The Chi-Chi earthquake not only helped to
identify a very specific research agenda for collaboration between MCEER and NCREE, it
provided an opportunity for MCEER and the PEER Center to coordinate expertise and work
together. The earthquake was devastating to the people of Taiwan, but the positive outcome
is that new research opportunities have been identified, our team efforts have been
enhanced, and experts from a variety of earthquake hazard mitigation centers have been
brought together.
1.1 References
Loh, C.H. and Tsay, C-Y. (forthcoming), "Responses of
Earthquake Engineering Research Community on the Chi-Chi (Taiwan)
Earthquake,"submitted to EERI Spectra.
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