Detection and Velocimetry of Floating Wood for Flood Disaster Risk Management Using Electromagnetic Imaging

Proceedings

article

Christopher Gomez¹  Norifumi Hotta³  Shusuke Miyata⁴  Balazs Bradak¹  Mikito Kataoka¹  Kensuke Ashikaga¹  Frans C. Persendt⁵ 

[1] Sabo Laboratory, Faculty of Oceanology, Kobe University;Centre of Natural Hazards and Disaster Risk, Gadjah Mada University;Department of Forest Science, Graduate School of Agricultural and Life Sciences, University of Tokyo;Disaster Prevention Research Institute, Kyoto University;Centre for Innovation in Learning and Teaching, University of Namibia

关键词: wood;    driftwood;    in-flow wood monitoring;    radar;    river;    flood;   

DOI  :  10.3390/IECG2022-14264

学科分类：社会科学、人文和艺术（综合）

来源: mdpi

【 摘 要 】

Wood travelling in rivers is a major hazard to lives and infrastructures, because tons of wood material can travel nearing the speed of the flood flow. If post-event mapping, detection and numerical simulation have made important progress, detecting in-flow driftwood in all weather and at all times still presents several challenges. The present work aims to expand the capacity to detect in-flow wood by adapting the ground-penetrating radar electromagnetic method. The laboratory test was carried out over a water circulation flume using an 800 MHz nominal frequency antenna sampling at 100 Hz and a video camera set on top of the flume to measure the average velocity of the wood logs. A set of single wood logs of 20 cm in length travelled underneath the antenna. The GPR results have demonstrated that the method had the potential to detect moving wood, and that it could “see” underneath the water to the shallow flume floor. The experiments resulted in the ability to count wood travelling underneath the antenna, and the instantaneous velocity was obtained with velocities ranging from 0.307 to 0.352 m/s, which was slightly higher than the average velocity measured from video imaging. This difference is explained by the in-flow acceleration of the wood after its introduction into the flume.

【 授权许可】

CC BY