2024 Volume 80 Issue 16 Article ID: 23-16090
We investigated the effect of the sand component with a diameter on the order of 0.1 mm (about 0.01 times a debris flow depth, which is the major grain-sized component of a debris flow) on the concentration of coarser particles at the flow’s front. As the experimental results, it was suggested that the sand component in the flow’s interior was contributed to grain size segregation due to the "dynamic sieving" (i.e., the component passed through the interstitial spaces between gravels in the flow’s interior and fell into the lower layers) in the same manner as the other grain sized components. It was also suggested that the concentration of coarser particles at the flow’s front could be estimated by using the ratio of flow depth to average grain size, the dimensionless shear rate, and the uniformity coefficient of the debris flow material, regardless of the content ratio of the sand component in the material.
