中文摘要：

沟岸被侧蚀掉的松散物质会通过动量交换将能量传递给龙头,从而影响泥石流的形成和运动过程。前人建立了许多模型来研究泥石流的侵蚀过程对泥石流形成和运动过程的影响,但是模型中大多以底蚀作用为前提条件。通过侧蚀模型和底蚀模型两种水槽实验的对比,针对泥石流的形成和运动过程展开研究。实验发现侧蚀作用更有利于泥石流的形成和运动,泥石流的龙头高度和速度都有波动特征,但侧蚀作用使得这种波动特征更加明显。侧蚀作用使得泥石流的龙身速度更快于龙头速度,龙身颗粒源源不断地堆积于龙头,使得龙头有较大的高度和附加坡降,因此,侧蚀条件下龙头的速度更快。

英文摘要：

The bank erosion of sediment through the exchange of momentum and energy transfer within the debris flow affects the unstable motion of the debris flow. Many models have been established to study the impact of erosion on debris flow initiation and motion,but most of the models were based on bed erosion. This paper analyzed the process of unstable motion of debris flows through an experimental flume to contrast bank erosion-dominated conditions and bed erosion-only conditions. The experiments showed that bank erosion enhanced the formation and propagation of debris flows. The height and velocity of the debris flows fluctuated along the path under both conditions. However,bank erosion made the motion fluctuation more obvious. Bank erosion usually occurred at the body of the debris flow and the particles moved more rapidly in the body than in the head,resulting in rapid growth of the head by the contribution of particles from the body. The height and additional gradient of the bank erosion-dominated debris flows were higher than those of the bed erosion-only debris flows. So the velocity of debris flow for bank erosion-dominated conditions was higher than that for bed erosion-only conditions.