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Loess disaster chains on the Heifangtai Platform, China, cause frequent loess landslides and form landslide dams, thus obstructing rivers. In addition, the failure of landslide dams causes loess mudflows and other related disasters. In this study, the influences of different inflow rates on the failure process and triggering mechanisms of loess landslide dams were explored using five sets of model experiments. These experimental results revealed that the failure of loess landslide dams occurs through overtopping and piping failure, or overtopping failure. Overtopping and piping failure can be divided into infiltration, seepage channel development, break overflow, and rebalancing. When the inflow rate was < 1.0 L/s, the water had enough time to penetrate the dam, and the fine particles of loess were continuously transported to the backwater slope to form several complete seepage channels. The overlying soil in the channel then collapsed and slipped, which caused the dam failure. Overtopping failure can be divided into break initiation, acceleration, and rebalancing stages. When the inflow rate was > 1.0 L/s, the water could not penetrate the dam in time. Overtopping failure primarily involves horizontal and downward erosion of the breach. The inflow rate was positively correlated with soil transport, peak flow velocity, and peak bulk density based on the experimental data. The bulk density of the failure mudflow was categorized into slow increase, transition, and attenuation stages based on our experimental results. In addition, by analyzing the volume and stability of residual dams, the likelihood and damage degree of secondary hazards after the dam failure were initially explored. This study provides a scientific basis for relevant studies on loess landslide dam failure.

来源平台：LANDSLIDES