Articles | Volume 18, issue 1
Research article
04 Jan 2018
Research article |  | 04 Jan 2018

Detection of collapsed buildings from lidar data due to the 2016 Kumamoto earthquake in Japan

Luis Moya, Fumio Yamazaki, Wen Liu, and Masumi Yamada

Abstract. The 2016 Kumamoto earthquake sequence was triggered by an Mw 6.2 event at 21:26 on 14 April. Approximately 28 h later, at 01:25 on 16 April, an Mw 7.0 event (the mainshock) followed. The epicenters of both events were located near the residential area of Mashiki and affected 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 16 April mainshock by airborne light detection and ranging (lidar) flights. Different methods were evaluated to identify collapsed buildings from the DSMs. The change in average elevation within a building footprint was found to be the most important factor. Finally, the distribution of collapsed buildings in the study area was presented, and the result was consistent with that of a building damage survey performed after the earthquake.

Short summary
On 14 April 2016, an Mw 6.5 earthquake occurred in Kumamoto prefecture, Japan (foreshock). About 28 h later, another earthquake of Mw 7.0 occurred (mainshock). The earthquake produced extensive losses to the infrastructure. This paper shows the extraction of collapsed buildings from a pair of airborne lidar data recorded before and after the mainshock. A number of methods were applied and their performances were evaluated by comparison with actual data obtained from a field survey.
Final-revised paper