Erosion characteristics of landslide deposits and overtopping-induced breach mechanisms of landslide dam

Key Points

• This research aims to explore the erosion characteristics of landslide dam deposits and the mechanisms of breach evolution during overtopping.
• Conducted flume model experiments on landslide dam breaching under overtopping.
• Analyzed the effects of grain size distribution and relative density on breach development.
• Established an erosion rate formula considering dynamic changes in the erosion coefficient.
• Breach formation rate was significantly influenced by relative density, with minor effects on breach morphology.
• Breach morphology evolved with increased coarse particle content, displaying steep ledges, scour pits, and linear forms.
• Peak flow rate positively correlated with the uniformity coefficient of the landslide material; the duration of breaching negatively correlated with average particle size.