泥石流的阵性波状运动

首先描述了在云南东川蒋家沟观测到的在粘性泥石流运动过程中的铺床作用，阵次交替的波状运动，以及相关的波的分化、叠加等现象。然后具体分析了阵性波不同部分的速度分布特征，给出了泥石流龙身部分的速度剖面示意图，并提出龙头是以滚动方式在残留层上运动的。两者间存在物质循环流动。由实测数据推算的波速表明阵性波是一种急流。最后从波的空间形态和传播速度的角度将泥石流的波状运动分为缓波、滚动短波和滚动长波。

Characteristics of Debris-flow Surge

Debris Flows in nature, for example in Jiangjia Valley, were often observed moving in form of surge which is considered as a kind of wave in this paper. At the beginning, surges smooth rough bed and produce a residual layer up on which sub sequent surges move without loss of material and with high velocity. Separation and superposition of the surges also occur in the event. The velocity distribution in different parts of surge is discussed and the velocity profile in the body of surge can be divided into three zones. Based on velocity distribution and the fact that mud surface of the residual layer keeps still before the front of surge reaches we propose that there is a circulation flow between the front of surge and the residual layer. The two would exchange material: the front is falling and the remainder is involved. Estimated wave velocity from measured data indicates that the surge is a supercritical flow which only propagates toward downstream. Finally the wave moments of debris flows are classified into subcritical wave, short roll wave and long roll wave according to their spatial shape and propagation velocity. The last two are just that so-called surge.