Comparison of 2D debris-flow simulation models with field events

Abstract

Three two-dimensional (2D) debris-flow simulation models are applied to two large welldocumented debris-flow events which caused major deposition of solid material on the fan. The models are based on a Voellmy fluid rheology reflecting turbulent-like and basal frictional stresses, a quadratic rheologic formulation including Bingham, collisional and turbulent stresses, and a HerschelYBulkley rheology representing a viscoplastic fluid. The rheologic or friction parameters of the models are either assumed a priori or adjusted to best match field observations. All three models are capable of reasonably reproducing the depositional pattern on the alluvial fan after the models have been calibrated using historical data from the torrent. Accurate representation of the channel and fan topography is especially important to achieve a good replication of the observed deposition pattern.

Debris flow run-out simulation and analysis using a dynamic model

“…Naef et al, 2006;Rickenmann et al, 2006;Hürlimann et al, 2008). Some of the rheological models frequently used to describe the behavior of debris flows are (e.g., Naef et al, 2006;Beguería et al, 2009;Hungr and McDougall, 2009): 1) the Coulomb frictional resistance; 2) the 15 Bingham model; 3) the Coulomb-Viscous; and (4) the Voellmy frictional-turbulent resistance.…”

Dispersive Pressure, Boundary Jerk and Configurational Changes in Debris Flows

“…The flow behavior of the mixture is defined by the interaction of the granular solid with the basal boundary as well as the viscous action of the muddy fluid; see Fig. 1 [Iverson, 1997]. Single phase debris flow models treat the mixture as a bulk material, using simple rheological models to describe the relationship between shear S and deformation gradients in the slope parallel direction [Savage and Hutter, 1989;Hungr, 1995;Rickenmann et al, 2006;Takahashi, 2007]. Two-phase models are similar except that they separate the flow material into solid and fluid components, positing separate mass and momentum balances and therefore applying different rheological laws for each phase.…”

GIS-based two-dimensional numerical simulation of rainfall-induced debris flow

“…Many researchers have developed rheological models for mudflows and debris flows. Theses models can be classified as: Newtonian models (Johnson, 1970;Trunk et al, 1986;Hunt, 1994;Hungr, 1995;Rickenmann, 1999), Bingham model (Johnson, 1970;O'Brien and Julien, 1988;Liu and Mei, 1989;Jan, 1997;Whipple, 1997;Fraccarollo and Papa, 2000;Pastor et al, 2004), Herschel-Bulkley model García, 1997, 1998;Imran et al, 2001;Remaître et al, 2005;Rickenmann et al, 2006), generalized viscoplastic model (Chen, 1988), dilatant fluid models (Bagnold, 1954;Takahashi, 1978Takahashi, , 1991Mainali and Rajaratnam, 1994), dispersive or turbulent stress models (Arai and Takahashi, 1986;O'Brien and Julien, 1988;Hunt, 1994), biviscous modified Bingham model (Dent and Lang, 1983), and frictional models (Iverson, 1997;Chen and Lee, 1999;Arattano and Franzi, 2003;Pastor et al, 2004;Rickenmann et al, 2006;Naef et al, 2006). Takahashi and Tsujimoto (1984) presented a twodimensional finite difference model for debris flows based on a dilatant-fluid model coupled with coulomb flow resistance, and modified the model to include turbulence (Taka-hashi et al, 1991(Taka-hashi et al, , 1992.…”

“…Pudasaini and Hutter (2006) provided a survey and discussion about the motion of avalanche-like flows from initiation to run out. Rickenmann et al (2006) compared three two-dimensional debris-flow simulation models with field events, and these models are based on a Voellmy fluid rheology reflecting turbulent-like and basal frictional stresses, a quadratic rheologic formulation including Bingham, collisional and turbulent stresses, and a Herschel-Bulkley rheology representing a viscoplastic fluid.…”