Preprint Article Version 1 This version is not peer-reviewed

An 1-D Integrated Hydro-Mechanical Model to Unravel Different Hydrological Triggering Processes of Debris Flows

Version 1 : Received: 4 January 2018 / Approved: 5 January 2018 / Online: 5 January 2018 (07:54:11 CET)
Version 2 : Received: 11 June 2018 / Approved: 13 June 2018 / Online: 13 June 2018 (08:37:32 CEST)

How to cite: van Asch, T.W.; Yu, B.; Hu, W. An 1-D Integrated Hydro-Mechanical Model to Unravel Different Hydrological Triggering Processes of Debris Flows. Preprints 2018, 2018010032 (doi: 10.20944/preprints201801.0032.v1). van Asch, T.W.; Yu, B.; Hu, W. An 1-D Integrated Hydro-Mechanical Model to Unravel Different Hydrological Triggering Processes of Debris Flows. Preprints 2018, 2018010032 (doi: 10.20944/preprints201801.0032.v1).

Abstract

Many studies, which try to analyze the meteorological threshold conditions for debris flows ignore the type of initiation. This paper focuses on the differences in hydrological triggering processes of debris flows in channel beds of the source areas. The different triggering processes were studied in the laboratory and by model simulation on the field scale. The laboratory experiments were carried out in a flume, 8 m long and a width of 0.3 m. An integrated hydro-mechanical model was developed, describing Hortonian and Saturation overland flow, through flow, maximum sediment transport and failure of bed material. The model was tested on the processes observed in the flume. The flume experiments show a sequence of hydrological processes triggering debris flows, namely erosion and transport by intensive overland flow and by infiltrating water causing failure of channel bed material. Model simulations carried out on a schematic hypothetical source area of a catchment show that the type and sequence of these triggering processes are determined by slope angle and the hydraulic conductivity of the bed material. It was also clearly demonstrated that the type of initiation process and the geometrical and hydro-mechanical parameters may have a great influence on rainfall intensity-duration threshold curves, indicating the start of debris flows.

Subject Areas

triggering of debris flows; overland flow; infiltration; laboratory experiments; modelling; rain intensity-duration threshold curves

Readers' Comments and Ratings (0)

Leave a public comment
Send a private comment to the author(s)
Rate this article
Views 0
Downloads 0
Comments 0
Metrics 0
Leave a public comment

×
Alerts
Notify me about updates to this article or when a peer-reviewed version is published.