Miao Huo

Debris flow erosion is key to the escalation of potential hazards, which may jeopardize the sustainable development of nearby human habitats. However, studies pertaining to this issue are impeded by the intricate interactions of flow and sediment. Thus, this study introduces an unresolved CFD-DEM coupled simulation primarily relying on a classical numerical simulation and a physical experiment to study the critical erosion process of debris flows on a dry basal sediment under laboratory scale. Results indicate that three layers of substrate bed can be verified during the erosion process, and there is a positive correlation between the erosion depth and the particle size with the Froude number of debris flow, as well as between the erosion length and the critical entrainment transport with the total mass of debris flow. In addition, thresholds for the collisional point load and the impact energy of debris flow head, which are essential for predicting the attenuating rates of erosive depth and the critical entrainment transport, have been proposed based on data regressions derived from power functions. The coupled numerical approach is capable of accurately simulating the erosion behavior of debris flows similarly to physical model experiments, thereby providing both theoretical and practical insights into the dynamics of erosion.

This study addresses the key issue of the interaction between debris flows and flexible barriers based on small-scale experiments for which both the flowing mixture and the barrier were designed to achieve similitude with real situations in Alpine environments. The considered debris consisted of a large solid fraction mixture with large and angular particles, flowing down a moderately inclined flume and resulting in near-critical flows, with a Froude number in the 0.9–2 range. The flexible barrier model consisted in 3D printed cables and net. The flow characteristics, evolution and deposition after contact with the barrier as well as the deformation and the loading experienced by the barrier were addressed varying the flume inclination and released mass. Four different interaction modes between the flow and the barrier are identified increasing the flow kinematics. A model based on the hydrostatic pressure assumption reveals relevant for estimating the total force exerted on the barrier when all the released material is trapped. This force doubles in case there is barrier overflow.

Debris flow erosion is key to the escalation of potential hazards, which may jeopardize the sustainable development of nearby human habitats. However, studies pertaining to this issue are impeded by the intricate interactions of flow and sediment. Thus, this study introduces an unresolved CFD-DEM coupled simulation primarily relying on a classical numerical simulation and a physical experiment to study critical erosion process of debris flows on a dry basal sediment under laboratory-scale. Results indicate that three layers of substrate bed can be verified during the erosion process, and there is a positive correlation between the erosion depth and the particle size with the Froude number of debris flow, as well as between the erosion length and the critical entrainment transport with the total mass of debris flow. In addition, thresholds for the collisional point load and the impact energy of debris flow head, which are essential for predicting the attenuating rates of erosive depth and the critical entrainment transport, have been proposed based on data regressions derived from power functions. The coupled numerical approach is capable of accurately simulating the erosion behavior of debris flows similarly to physical model experiments, thereby providing both theoretical and practical insights into the dynamics of erosion.

This study addresses the key issue of the interaction between debris flows and flexible barriers based on small scale experiments for which both the flowing mixture and the barrier were designed to achieve similitude with real situations in Alpine environments. The considered debris consisted of a large solid fraction mixture with large and angular particles, flowing down a moderately inclined flume and resulting in near critical flows, with a Froude number in the 0.9–2 range. The flexible barrier model consisted in 3D printed cables and net. The flow characteristics, evolution and deposition after contact with the barrier as well as the deformation and the loading experienced by the barrier were addressed varying the flume inclination and released mass. Four different interaction modes between the flow and the barrier are identified increasing the flow kinematics. A model based on the hydrostatic pressure assumption reveals relevant for estimating the total force exerted on the barrier when all the released material is trapped. This force doubles in case there was barrier overflow.

This study addresses the key issue of the interaction between debris flows and flexible barriers based on small scale experiments for which both the flowing mixture and the barrier were designed to achieve similitude with real situations in Alpine environments. The considered debris consisted of a large solid fraction mixture with large and angular particles, flowing down a moderately inclined flume and resulting in near critical flows, with a Froude number in the 0.9–2 range. The flexible barrier model consisted in 3D printed cables and net. The flow characteristics, evolution and deposition after contact with the barrier as well as the deformation and the loading experienced by the barrier were addressed varying the flume inclination and released mass. Four different interaction modes between the flow and the barrier are identified increasing the flow kinematics. A model based on the hydrostatic pressure assumption reveals relevant for estimating the total force exerted on the barrier when all the released material is trapped. This force doubles in case there was barrier overflow.

This study addresses the key issue of the interaction between debris flows and flexible barriers based on small scale experiments for which both the flowing mixture and the barrier were designed to achieve similitude with real situations in Alpine environments. The considered debris consisted of a large solid fraction mixture with large and angular particles, flowing down a moderately inclined flume and resulting in near critical flows, with a Froude number in the 0.9–2 range. The flexible barrier model consisted in 3D printed cables and net. The flow characteristics, evolution and deposition after contact with the barrier as well as the deformation and the loading experienced by the barrier were addressed varying the flume inclination and released mass. Four different interaction modes between the flow and the barrier are identified increasing the flow kinematics. A model based on the hydrostatic pressure assumption reveals relevant for estimating the total force exerted on the barrier when all the released material is trapped. This force doubles in case there was barrier overflow.

This study addresses the key issue of the interaction between debris flows and flexible barriers based on small scale experiments for which both the flowing mixture and the barrier were designed to achieve similitude with real situations in Alpine environments. The considered debris consisted of a large solid fraction mixture with large and angular particles, flowing down a moderately inclined flume and resulting in near critical flows, with a Froude number in the 0.9–2 range. The flexible barrier model consisted in 3D printed cables and net. The flow characteristics, evolution and deposition after contact with the barrier as well as the deformation and the loading experienced by the barrier were addressed varying the flume inclination and released mass. Four different interaction modes between the flow and the barrier are identified increasing the flow kinematics. A model based on the hydrostatic pressure assumption reveals relevant for estimating the total force exerted on the barrier when all the released material is trapped. This force doubles in case there was barrier overflow.

This study addresses the key issue of the interaction between debris flows and flexible barriers based on small scale experiments for which both the flowing mixture and the barrier were designed to achieve similitude with real situations in Alpine environments. The considered debris consisted of a large solid fraction mixture with large and angular particles, flowing down a moderately inclined flume and resulting in near critical flows, with a Froude number in the 0.9–2 range. The flexible barrier model consisted in 3D printed cables and net. The flow characteristics, evolution and deposition after contact with the barrier as well as the deformation and the loading experienced by the barrier were addressed varying the flume inclination and released mass. Four different interaction modes between the flow and the barrier are identified increasing the flow kinematics. A model based on the hydrostatic pressure assumption reveals relevant for estimating the total force exerted on the barrier when all the released material is trapped. This force doubles in case there was barrier overflow.

This study addresses the key issue of the interaction between debris flows and flexible barriers based on small scale experiments for which both the flowing mixture and the barrier were designed to achieve similitude with real situations in Alpine environments. The considered debris consisted of a large solid fraction mixture with large and angular particles, flowing down a moderately inclined flume and resulting in near critical flows, with a Froude number in the 0.9–2 range. The flexible barrier model consisted in 3D printed cables and net. The flow characteristics, evolution and deposition after contact with the barrier as well as the deformation and the loading experienced by the barrier were addressed varying the flume inclination and released mass. Four different interaction modes between the flow and the barrier are identified increasing the flow kinematics. A model based on the hydrostatic pressure assumption reveals relevant for estimating the total force exerted on the barrier when all the released material is trapped. This force doubles in case there was barrier overflow.

Research on the scraping effects of rock–ice avalanches remains relatively limited. This study investigates the evolution of rock–ice avalanches with varying ice content and initial accumulation forms during motion, scraping, and deposition using laboratory physical model experiments. Changes in pre- scraping velocity, scraping length, scraping depth, maximum deposition length, and deposition thickness were analyzed as functions of ice content. The analysis revealed the influence of ice content and initial accumulation on scraping effects, as well as on motion and deposition characteristics. The experimental results indicate that, compared to typical debris flows (without ice), the presence of ice significantly enhances the mobility, deposition features, and scraping effects of rock–ice avalanches. Through analysis, it is shown that the low friction of ice debris enhances the kinetic energy of ice-rock debris flows, thereby increasing the energy required for scraping.