Detection of collapsed buildings due to the 2016 Kumamoto, Japan, earthquake from Lidar data

Abstract

Abstract. The 2016 Kumamoto earthquake sequence was triggered by an Mw 6.2 event at 21:26 on April 14. Approximately 28 hours later, at 1:25 on April 16, an Mw 7.0 event (the mainshock) followed. The epicenters of both events were located 10 near the residential area of Mashiki town and the region nearby. Due to very strong seismic ground motion, the earthquake produced extensive damage to buildings and infrastructure. In this paper, collapsed buildings were detected using a pair of digital surface models (DSMs), taken before and after the April 16 mainshock by airborne light detection and ranging (Lidar) flights. Different methods for extracting the collapsed buildings from the data were evaluated, and the change of average elevations within a building footprint was found to be the most important feature. Finally, the distribution of collapsed 15 buildings in the study area was presented, and the result was consistent with that of a building damage survey performed after the earthquake.