Effect of the Voellmy Coefficients on Determining Run-out Distance: A Case Study at Uzungöl, Turkey

Yıl 2007, Cilt: 20 Sayı: 3, 79 - 85, 29.03.2010

Önder Koçyiğit İbrahim Gürer

Öz

In this study, the traditional Voellmy model which has been widely applied since 1956 for all types of avalanches was used in defining the path length to compute the run-out distance of avalanches that occurred in UzungÖl. UzungÖl, a village which is located in a valley of North-Eastern Anatolia was chosen as a pilot project area since some fatal snow avalanches occurred in this area in the 1992 winter season. Due to limited data and field observations, dynamic and turbulence friction coefficients were taken as µ= 0.155 and  ξ= 500 m/s²,respectively, for well defined slopes. Although it wasn’t possible to check most of the computed values which need to be measured during an avalanche, the run-out distance was found to be determined quite accurately. A number of the Voellmy coefficients were tested to  compute the run-out distance, and the effect of those coefficients on the hydraulic parameters of the avalanche, such as discharge, velocity and depth, was investigated. 

 

Key Words: Voellmy coefficients, Run-out distance, Avalanche dynamic, UzungÖl 

Anahtar Kelimeler

Voellmy coefficients, Run-out distance, Avalanche dynamic, Uzungöl

Kaynakça

• Margreth, S., “Avalanche Forecasting, Mapping, Zoning and Paravalanche Construction Technologies”, Turkish-French-Swiss Tesearch and Development Project Report 2, General Directorate of Disasters Affairs, Ankara, 22 p., (1994).
• Buser, O. and Frutiger, H., “Observed Maximum Run-out Distance of Snow Avalanches and The Determination of The Friction Coefficients µ and ξ”, Journal of Glaciology, 26(94): 121-130 (1980).
• Voellmy, A., “Uber die Zerstoerunskraft von Lawinen: Schweizerische Bauzeitung”, Jahrg. 73, No:12, (English translation by R.E. Tate: On the Destructive Force of Avalanche : U.S. Department of Agriculture, Forest Service, Alta Avalanche Study Center Translation No 2, 1964), (1955).
• Salm, B. and Gubler, H.U., “Calcul Des Avalanches: Une Methode Didactique Pour le Calcul Pratique”, , Tradiction d’une Publication de Eigdenössichen Institut Für Schnee Und Lawinenforschung, Nr. 47, CEMAGREFNivologie, 26p. (1990).
• Salm, B., “Fliessübergange Und Aslaufstrecken von Lawinen”, Interner Bericht des Eidg. Institutes für Schnee und Lawinenforschung, Nr. 566, 45p., (1979).
• Bozhinskiy, A.N. and Losev, K.S., “The Fundamentals of Avalanche Science”, Mitteilungen des Eidgenössischen Institutes für Schnee und Lawinenforschung, 55, 280 p. (Translation of “Osnovy Lavinovedeniya”, by C. Bartelt Leningrad, Gidrometeoizdat), (1998).
• Kozik, S.M., “Computing Snow Avalanche Motion (in Russian)”, Gidrometeoizdat, Leningrad, 76 p., (1962)
• Salm,B., “A Short and Personal History of Snow Avalanche Dynamics”, Cold Region Science and Technology, 39: 83-92 (2004).
• Barbolini M., Gruber U., Keylock, C.J., Naaim, M. and Savi, F, “Application of Statistical and Hydraulic-continuum Dense-snow Avalanche Models to Five Real European Sites”, Cold Regions Science and Technology, 31:133-149, (2000).
• Grigorian, S., Eglit, M. and Yakimov, Y., “A new Formulation and Solution of the Problem of the Motion of Snow Avalanches”, Trudy Vycokogornogo Geofizicheskogo Instituta (in Russian), 12 :104-113, (1967).
• Perla, R., Cheng, T. and McClung, D., “A Twoparameter Model of Snow Avalanche Motion”, Journal of Glaciology, 26(94): 197-207, (1980).
• Brugnot, G. and Pochat, R., “Numerical Simulation Study of Avalanches”, Journal of Glaciology, 27(95): 77-88, (1981).
• Maeno, N. and Nishimura, K., “Numerical Computation of Snow Avalanche Motion in a Three-dimensional Topography, Low Temperature Science, 46: 99-110, (1987).
• Norem, H., Irgens, F. and Schieldrop, B., “A Continuum Model for Calculating Snow Avalanche Velocities”, International Association of Hydrological Sciences, Symposium at Davos 1986 – Avalanche Formation, Movements and Effects, Publication 162, IAHS Press, Wallingford, Oxfordshire, UK., 363-379, (1987).
• Norem, H., Irgens, F. and Schieldrop, B., “Simulation of Snow Avalanche Flow in Run-out Zones”, Annals of Glaciology, 13: 218-225, (1989).
• Sovilla, B., “Field Experiments and Numerical Modelling of Mass Entrainment and Deposition Processes in Snow Avalanches”, PhD. Thesis, Swiss Federal Institute of Technology, Zurich, 189 p. (2004).
• Lied, K. and Bakkehoi, S., “Empirical Calculations of Snow Avalanche Run-out Distance Based on Topographic Parameters”, Journal of Glaciology, 26(94):165-177, (1980).
• Ancey, C., Gervasoni, C. and Meunier, M., “Computing Extreme Avalanches”, Cold Regions Science and Technology, 39: 161-180, (2004).
• Sovilla, B., Margreth, S. and Bartelt, P., “On Snow Entrainment in Avalanche Dynamics Calculations”, Cold Regions Science and Technology, 47: 69-79, (2007).
• De Toni, S. and Scotton, P., “Two-dimensional Mathematical and Numerical Model for Dynamics of Granular Avalanches”, Cold Regions Science and Technology, 43: 36-48, (2005).
• Barpi, F., “Fuzzy Modelling of Powder Snow Avalanches”, Cold Regions Science and Technology, 40: 213-227, (2004).
• Turnbull, B. and Bartelt, P., “Mass and Momentum Balance Model of a Mix Flowing/Powder Snow Avalanche”, Surveys in Geophysics, 24: 465-477, (2003).
• Schaerer, P.A., “Friction Coefficients and Speed of Flowing Avalanches”, Symposium at Grindelwald 1974 – Snow Mechanics, International Association of Hydrological Sciences, Publication 114, IAHS Press, Wallingford, Oxfordshire, UK., 425-437, (1975).
• Mears A.I., “Snow-Avalanche Hazard Analysis for Land-Use Planning and Savage, St.B., Flow of Granular Materials”, Theoretical and Applied Mechanics, IUTAM, 241-266, (1989).
• Herman, F. and Hutter, K., “Laboratory Experiments on the Dynamics of Powder-snow Avalanches in the Run-out Zone”, Journal of Glaciology, 37(126): 281-295, (1991).
• Mears A.I., “Snow-Avalanche Hazard Analysis for Land-Use Planning and Engineering”, Colorado Geological Survey, Department of Natural Resources, Denver, USA, Bulletin 49, 28-31, (1992)