Numerical Simulation of Debris Flows Triggered from the Strug Rock Fall Source Area, W Slovenia

Mikoš, Matjaž (author), Fazarinc, Rok (author), Majes, Bojan (author), Rajar, Rudolf (author), Žagar, Dušan (author), Krzyk, Mario (author), Hojnik, Tomaž (author), Četina, Matjaž (author)

The Strug landslide was triggered in December 2001 as a rockslide, followed by a rock fall. In 2002, about 20 debris flows were registered in the Kosec village; they were initiated in the Strug rock fall source area. They all flowed through the aligned Brusnik channel, which had been finished just before the first debris flow reached the village in April 2002. Debris flow events were rainfall-induced but also governed by the availability of rock fall debris in its zone of accumulation. After 2002 there was not enough material available for further debris flows to reach the village. Nevertheless, a decision was reached to use mathematical modeling to prepare a hazard map for the village for possible new debris flows. Using the hydrological data of the Brusnik watershed and the theological characteristics of the debris material, 5 different scenarios were defined with the debris flow volumes from 1000 m(3) to a maximum of 25 000 m(3). Two mathematical models were used, a one-dimensional model DEBRIF-1D, and a two-dimensional commercially available model FLO-2D. Due to the lack of other field data, data extracted from available professional films of debris flows in 2002 in the Kosec village were used for model calibration. The computational reach was put together from an 800-m long upstream reach and 380-m long regulated reach of the Brusnik channel through the village of Kosec. Both mathematical models have proved that the aligned Brusnik channel can convey debris flows of the volume up to 15 000 m(3). Under the most extreme scenario a debris flow with 25 000 m3 would locally spill over the existing levees along the regulated Brusnik channel. For this reason, additional river engineering measures have been proposed, such as the raising of the levees and the construction of a right-hand side sedimentation area for debris flows at the downstream end of the regulated reach.

• Language: English
• Keywords: debris flows, mathematical modelling, complex landslides, hazard assessment, torrent control, sensitivity analysis
• Typology: 1.01 - Original Scientific Article
• Organization: FGG - Faculty of Civil and Geodetic Engineering
• Publisher: European Geosciences Union
• Year: 2006
• Number of pages: Str. 261-270
• Numbering: Vol. 6, No. 2
• PID: 20.500.12556/RUL-32166
• UDC: 556:624
• ISSN on article: 1561-8633
• COBISS.SI-ID: 3077729
• Publication date in RUL: 10.07.2015

Record is a part of a journal

• Title: Natural hazards and earth system sciences
• Shortened title: Nat. hazards earth syst. sci.
• Publisher: European Geophysical Society
• ISSN: 1561-8633
• COBISS.SI-ID: 2666081

Secondary language

• Language: English
• Keywords: drobirski tokovi, matematično modeliranje, kompleksni zemeljski plazovi, ocena tveganja, urejanje hudournikov, analiza občutljivosti