Managing avalanches using cost–benefit–risk analysis

Malmbanan, the Swedish Iron Ore Line, runs through rough terrain including high mountains, peat, terraces situated on fjords, and numerous short bridges and culverts. The area is sub-arctic and mountainous, with a sharp gradient between the part with a maritime climate and that with a continental cl...

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Bibliographic Details
Published in:Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit
Main Author: Larsson-Kråik, Per-Olof
Format: Article in Journal/Newspaper
Language:English
Published: SAGE Publications 2012
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Online Access:http://dx.doi.org/10.1177/0954409712447168
http://journals.sagepub.com/doi/pdf/10.1177/0954409712447168
http://journals.sagepub.com/doi/full-xml/10.1177/0954409712447168
Description
Summary:Malmbanan, the Swedish Iron Ore Line, runs through rough terrain including high mountains, peat, terraces situated on fjords, and numerous short bridges and culverts. The area is sub-arctic and mountainous, with a sharp gradient between the part with a maritime climate and that with a continental climate. Global warming and new climate conditions are increasing the risk of slab and snow avalanches. A cost–benefit–risk analysis, dealing with slab and snow avalanches, high spring temperatures with fast snow melting, high water levels and heavy rainfalls, was performed in 2001. A number of at-risk sections along the track were identified and some of the risks were later addressed with changes in the infrastructure and changes in train operation during bad weather conditions. During the past 10 years, the various actions taken have been continuously improved. An evaluation based on operational data shows a lower risk of trains running into hazard areas and better control of slab and snow avalanches. Other improvements are better control and monitoring of rock falls and a lowered risk for trains operating during bad weather conditions. The technical systems in use consist of instrumented arrays of poles placed along the track to indicate avalanches. Bridges have been built to permit avalanches to pass under the railway and artificial tunnels have been designed and constructed to allow avalanches to pass over the railway. Rock fall nets have been put into service and professional avalanche inspection teams have been used for risk evaluation during high-risk weather conditions.