Detection and analysis of avalanches using wave measurements

The road along the Oshlio-hillside is one of the most hazardous roads in Iceland due to rockfalL debris flows and avalanches. There arc 23 known avalanche tracks in the hillside. Below four of the tracks with the highest avalanche frequencies concrete avalanche sheds have been constructed to protect the road. When there is an avalanche threat in the Óshlið-hillside often many avalanches fall from different tracks in a short time and therefore it is likely that avalanches will hit the concrete sheds. Based on this knowledge a research project was initiated in February 1996 with the objective of developing a system to detect and ;nalyse avalanches that hit one of these sheds and to send a warning to a control station. Later the project was extended and two more tracks with no avalanche sheds were included. This paper describes the system and presents the first results of the research project.