Effect of Including Sand Component in a Debris Flow on Concentration of Coarser Particles at the Flow Front

We conducted flume experiments for a debris flow consisting of coarser particles, finer particles and sand, focusing on the concentration at front. Our experimental results revealed that front using sediment mixture with sand was less than without sand. This may be because including component in material contributed to smaller averaged interstice between layer particle size. These lead reduce falling volume or dispersion pressure rise respectively, resulting inhibition inverse grading formation. also suggested changing trend proportion depended relationship their size average flow. are consistent our previous consistency front, behavior can considered same manner as other coarser-sized components.