Simulating Debris Flow and Levee Formation in the 2D Shallow Flow Model D‐Claw: Channelized and Unconfined Flow

Debris flow runout poses a hazard to life and infrastructure. The expansion of human population into mountainous areas onto alluvial fans increases the need predict mitigate debris hazards. flows on unconfined can exhibit spontaneous self-channelization through levee formation that reduces lateral spreading extends distances compared unchannelized flows. Here we modify D-Claw shallow model in two ways are hypothesized generate levees. We evaluate these modifications with observations from large-scale flume experiment. investigate performance when including effect different friction sub-models, as well inclusion segregation effects granular permeability. Results show that, for wide range plausible input parameters, simulations promoted modeled formation, whereas without did not create Further, using forward predictive framework, were more likely better magnitude depth distance, simulation timing was affected by choice sub-model. Our results indicate permeability improve likelihood predictions prior an event occurring.