[S-SS07] Environmental Seismology: from deep earth to surface process

[SSS07-03] Seismic and Dynamic Properties of Granular Flows across Flow Regimes: Insights from Flume Experiments

*Yifei Cui¹, Xinzhi Zhou¹ (1.Tsinghua University)

Keywords:Granular flow, Flume experiments, Particle composition, Seismic response, Basal force characteristics, Flow regimes

Granular flows, such as landslides and rock avalanches, pose significant hazards in mountainous regions, necessitating precise modeling for disaster mitigation. This study investigates the influence of particle composition and flow regimes on granular flow dynamics, seismic response, and basal force characteristics through flume experiments. By varying particle size distributions and flume inclinations, we analyzed kinematic properties, seismic emissions, and their correlation with flow regimes. The results demonstrate that particle composition has a strong influence on mobility, with an optimal proportion of large particles enhancing flow efficiency. Seismic signals, including peak amplitude and power spectral density, are correlated with collisional stresses, exhibiting a biphasic positive trend. Basal force probability density functions (PDFs) reveal heavy - tailed distributions, indicating intermittent force transmission and significant fluctuations in collisional regimes. A unified framework based on the dimensionless amplitude parameter and the Savage number is utilized to interpret seismic responses. Frictional flows generate seismic signals through bulk impacts, while collisional flows produce them via inter - particle collisions, with basal forces reflecting regime transitions. This study enhances the understanding of granular flow dynamics by linking seismic and basal force characteristics to flow behavior. These findings improve seismic - based debris flow monitoring and hazard assessment, emphasizing the importance of basal force analysis in interpreting granular flows in natural environments.