STUDY ON BUILDING DAMAGE AROUND STRONG MOTION OBSERVATION SITES IN THE 2023 TURKEY–SYRIA EARTHQUAKE

On February 6, 2023, an M7.8 earthquake occurred with its epicenter in southern Turkey, followed by another large M7.5 earthquake on the same day. These earthquakes caused significant damage to buildings and human lives. In response, the JSPS KAKENHI project survey team, Architectural Institute of Japan, Japan Society of Civil Engineering, and Japan Geotechnical Society jointly dispatched a disaster survey team to the site from late March to early April 2023. To analyze the correlation between the characteristics of strong motion records and the tendency of damage to the surrounding buildings, we conducted field surveys of 211 buildings around eight strong motion observation sites where strong seismic motion was recorded. We obtained data on the structural type, number of stories, and damage grade of each building. Comparing the ratio of the number of "very heavy damage" and "destruction" buildings to the number of surveyed buildings at each observation site (collapse rate), we established a correlation between the magnitude of seismic ground motion and the collapse rate. In addition, when comparing the collapse rates of low-rise masonry structures and medium-to-high-rise reinforced-concrete moment-resisting frame structures, we confirmed that the tendencies of which the collapse rate is higher at each observation site are different. At a specific observation site, the dominant period of seismic ground motion and the natural period of surrounding buildings were similar, resulting in significant building damage.