earticle

영어

In steep mountainous areas, debris flows can entrain large boulders with various diameters. The boulder enriched flow front imparts highly collisional stresses on the soil bed during the flow. Although, they possess highly erosive potentials, all the eroded particles are not feasibly transported to downstream. The erosion and transport capacity of granular flows are influenced by its composition of grains. Since, it has not been explicitly accounted in the continuum models, the total volume of bed transport tends to be overestimated. Therefore, it is essential to characterize the mechanisms of frictional or collisional bed yielding, transport, and surface morphology, while incorporating erosion into mobility prediction tools for hazard assessment and designing protective structures based on flow characteristics. In this study, small-scale flume experiments were performed for granular flows having a wide range of particle variations between 25mm-60mm at different slope angles of 25o-30o. After the experiment, the surface morphology evolution due to the granular flows were also assessed by scanning the surface using the hand-held laser scanner. The results infer that, increasing the grain size leads to a reduction in transported mass, while increasing the flume angle enhance the mass transportation to the downstream. The surface scanning results show that erosion zones are more widely distributed at higher angles, in contrast to the more discrete distribution observed at shallower angles.