[H-DS07] Landslides and related phenomena

[HDS07-P09] Using new RIM material to investigate granular avalanches of irregular sand particles in slumping regime in a rotating drum

*Chien-Hsien Lee¹, Chi-Yao Hung¹ (1.National Chung Hsing University)

Keywords:granular avalanches, Refractive Index Matching material, Irregular particles

Granular flows in the slumping regime of a rotating drum are commonly applied to study the mechanism of geophysical flow, particularly in a landslide. In previous studies, the trigger mechanism with the regular particle is well investigated, but the irregular particle's effects are not entirely understood. In this study, we use a thin half-filled rotating drum (40 cm in diameter with 6 cm in width) operating in the slumping regime (below 0.05 rpm) to investigate the effect of irregular-shaped particles in the trigger mechanism. To gain optical access to the interior and perimeter, we use the refractive index matching material (irregular-shaped fused quartz and a blend of white mineral oils) to visualize and measure the internal structure. The motions of the particles are captured through a high-speed camera and a newly developed Particle Tracking Velocimetry (PTV) method. We propose probability distributions for the slumping frequency and the flow area by varying the rotation rate and particle size.