Debris flow run-out simulation and analysis using a dynamic model
Only two months after a huge forest fire occurred in the upper part of a valley located in central Portugal, several debris flows were triggered by intense rainfall. The event caused infrastructural and economic damage, although no lives were lost. The present research aims to simulate the run-ou...
Main Authors: | , , |
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Format: | Article |
Language: | English |
Published: |
Copernicus Publications
2018-02-01
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Series: | Natural Hazards and Earth System Sciences |
Online Access: | https://www.nat-hazards-earth-syst-sci.net/18/555/2018/nhess-18-555-2018.pdf |
Summary: | Only two months after a huge forest fire occurred in the upper part of a
valley located in central Portugal, several debris flows were triggered by
intense rainfall. The event caused infrastructural and economic damage,
although no lives were lost. The present research aims to simulate the run-out
of two debris flows that occurred during the event as well as to calculate
via back-analysis the rheological parameters and the excess rain involved. Thus,
a dynamic model was used, which integrates surface runoff, concentrated
erosion along the channels, propagation and deposition of flow material.
Afterwards, the model was validated using 32 debris flows triggered during
the same event that were not considered for calibration. The rheological and
entrainment parameters obtained for the most accurate simulation were then
used to perform three scenarios of debris flow run-out on the basin scale.
The results were confronted with the existing buildings exposed in the
study area and the worst-case scenario showed a potential inundation that may
affect 345 buildings. In addition, six streams where debris flow occurred in
the past and caused material damage and loss of lives were identified. |
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ISSN: | 1561-8633 1684-9981 |