Formation conditions of landslide dams triggered by incision of mine waste accumulations

【摘要】 The erosion and delivery processes of mine waste accumulations were reproduced through flume tests under 13 different experimental condition sets. Analysis of the flume test results showed that different scale model landslides, induced by the incision of mine waste accumulations, slipped into the channel and caused complete or partial blockages, with 28 complete blockages and 122 partial blockages observed during the flume tests. The failure of these temporary landslide dams amplified the peak discharge significantly, with the amplification more obvious when caused by the failure of a complete blockage compared to a partial blockage under the same experimental conditions. In order to explore the threshold conditions of a complete blockage, a new blockage index(Ibs) was developed to represent the degree of blockage. It was found that the threshold value of the blockage index for a complete blockage was around Ibs=4.0. What’s more, there was a significant negative correlation between the blockage index and the amplification coefficient of peak discharge caused by the failure of a landslide dam.These preliminary results are intended to provide a scientific basis for future research on the disaster prevention and mitigation of mine waste debris flows, as the processes and mechanisms underlying the erosion and delivery of mine waste accumulations by upstream flows along a gully have not yet been clearly identified.更多还原

【Abstract】 The erosion and delivery processes of mine waste accumulations were reproduced through flume tests under 13 different experimental condition sets. Analysis of the flume test results showed that different scale model landslides, induced by the incision of mine waste accumulations, slipped into the channel and caused complete or partial blockages, with 28 complete blockages and 122 partial blockages observed during the flume tests. The failure of these temporary landslide dams amplified the peak discharge significantly, with the amplification more obvious when caused by the failure of a complete blockage compared to a partial blockage under the same experimental conditions. In order to explore the threshold conditions of a complete blockage, a new blockage index(Ibs) was developed to represent the degree of blockage. It was found that the threshold value of the blockage index for a complete blockage was around Ibs=4.0. What’s more, there was a significant negative correlation between the blockage index and the amplification coefficient of peak discharge caused by the failure of a landslide dam.These preliminary results are intended to provide a scientific basis for future research on the disaster prevention and mitigation of mine waste debris flows, as the processes and mechanisms underlying the erosion and delivery of mine waste accumulations by upstream flows along a gully have not yet been clearly identified.更多还原