| Landslide dams are formed sometimes owing to the occurrence of landslides and debris flows. The presentstudy discusses their formation and breach processes based on the numerical simulation of debris flows.The simulation model employs a depth-averaged two-dimensional form of governing equations which arecomposed of the mass conservation equations for the flow body, bed sediment and momentum conservationequations for the flow. Bed shear stress and erosion rate terms involved in the governing equations playimportant roles in debris flow behavior. Phase shifting phenomena from a solid phase to fluid phase isincluded in evaluating the mobility of debris flows. The numerical model is applied to the landslide damformed within Ono River in Hita city after heavy rainfall in July 2017. The results suggest that the formationand breach processes of landslide dams are evaluated well by the numerical model. |
