Damage Survey and Residual Seismic Capacity Evaluation of Reinforced Concrete School Buildings after the 2018 Hokkaido Eastern Iburi Earthquake

ABSTRACT

In this study, a damage survey was conducted on the buildings of two schools located in the town of Abira, where a Japanese seismic intensity of 6 upper was recorded during the 2018 Hokkaido Eastern Iburi Earthquake. The damage classes of the reinforced concrete structural members and residual seismic capacity ratios were examined. Both schools had performed seismic evaluation and retrofitting before the earthquake, and no serious damage occurred, but flexural and shear cracks in columns and walls were observed. Analysis using drone photographs was conducted to perform crack detection and crack width evaluation and create point cloud models.

KEYWORDS:

• Reinforced concrete
• damage class
• residual seismic capacity ratio
• unmanned aerial vehicle (UAV)
• drone
• crack detection

Acknowledgments

We appreciate the Board of Education and the Construction Section of Abira for cooperating with the damage survey and providing documentation on the seismic evaluation of Schools A and B. We also thank to the teachers and staff of Schools A and B for supporting this survey. This study used the K-NET seismic observation record provided by National Research Institute for Earth Science and Disaster Resilience (NIED). The image analysis in this study was performed with the service provided by Research and Development Consortium of Crack Monitoring System for Road Structures. The GSI Maps provided by Geospatial Information Authority of Japan were used.

Disclosure Statement

The authors declare that there are no conflicts of interest related to this article to disclose.

Additional information

Funding

The present work was supported by the Japan Society for the Promotion of Science KAKENHI Grant number [JP18K19952].