The magnitude 6.4 southern Taiwan earthquake occurred near the city of Tainan, Taiwan, on February 5, 2016, causing severe damage, partial collapse, and full collapse of low-to-midrise reinforced concrete buildings. While the measures of ground motion intensity would have indicated moderate structural damage, instead ten reinforced concrete buildings collapsed and hundreds more have been reported to have severe damage as a consequence of the earthquake. This damage was surprising because Taiwan has made considerable investments into earthquake research, regulations, enforcement, and strengthening. To understand this discrepancy in reinforced concrete building performance, this Grant for Rapid Response Research (RAPID) will fund a team of researchers from the United States to travel to Taiwan to work with Taiwanese researchers to gather detailed building response data, including the observed damage and properties of building structures in quantifiable terms. Both damaged and undamaged buildings will be surveyed to produce a comprehensive data set that can be used to test hypotheses on causes of damage. The data set will be used to: (1) understand causes of building collapse, (2) identify building properties that increase probability of structural damage, (3) identify vulnerable structures in seismic areas, in particular older structures built prior to modern seismic design codes, and (4) study the relationship of the site response and building damage. Because Taiwan has adopted seismic design methodologies similar to those in the United States, this data set also will help improve understanding of the seismic vulnerability of reinforced concrete buildings in the United States.
The U.S. team will work with researchers from Taiwan's National Center for Research in Earthquake Engineering and National Cheng Kung University to gather data from 100 to 150 buildings affected by this earthquake. For each surveyed building, collected information will include: structural damage, geotechnical damage, structural configuration, key dimensions, building drawings, year of building code used for design, material properties, and for selected buildings, high-resolution image sequences to produce digital damage maps that can be used to quantify damage and performance in clear terms. Breaking with common practice, the team will survey both damaged and undamaged buildings, as well as retrofitted buildings. The project will produce a comprehensive data set, including information on ground motion (Taiwan has one of the densest networks of accelerometers in the world), geotechnical information, structural information, and observed performance. The data set will enable detailed engineering studies of specific buildings and sites. In total, the data set will form a "testbed" to: (1) evaluate state-of-the-art methodologies used to evaluate building vulnerability, including vulnerability to collapse, (2) develop new damage indicators for rapid screening of the built infrastructure, and (3) evaluate the effectiveness of retrofit strategies. The data set will be archived in the data repository on the DesignSafe-CI.org web site for broad use by researchers, educators, and the practicing engineering community in the United States, Taiwan, and other countries. This project will also train graduate students in post-earthquake field data collection and data archiving and curation.
