中文摘要：

黏土颗粒在泥石流中的含量并不大，但却显著地影响着泥石流的启动。在室内通过筛分配成9种不同黏粒含量级配的土体，在自行设计的模型槽内以1．64g／cm3（松散干密度），1．79、1．94g／cm3（天然干密度）3种干密度堆成边坡模型，在雨强为85mm／h下进行人工降雨试验，初步探讨了黏土颗粒含量对泥石流启动的影响，得到：黏粒含量在5％～18％时可以形成泥石流，其中黏粒含量10％时所需时间最短，低于5％或大于18％难以形成泥石流，黏粒含量具有临界性；填筑干密度越大，泥石流启动越困难，表现在启动时间长、深度浅、规模小、且填筑干密度不改变黏粒含量临界性；降雨条件下土体入渗率越高，泥石流越容易启动产流。通过试验的研究，可以深入揭示泥石流形成的内在机制，黏粒含量临界性为泥石流预测、预报提供了新思路。

英文摘要：

Content of clay particles in debris flow is not much, but it significantly affects the occurrence of debris flow. Indoor artificial rainfall experiments are carried out in self-designed model with nine different graded soils, three different dry densities （1.64 g/cm3 （loosely accumulation dry density）, 1.79 g/cm3, 1.94 g/cm3 （natural dry density））, rainfall intensity 85 ram/h, impact which content of clay particles on debris flow occurrence is preliminarily studied. As a result, it＇s found that debris flow can occur when content of clay particles is between 5% and 18%, it needs shorter time when content of clay particles is 10% than others; clay content has criticality. The greater the dry density of accumulation, the more difficult debris flows to occur with long start-up time, shallow depth and small scale, but accumulation dry density does not change the criticality of clay content. Under the condition of rainfall, the higher the soil infiltration rate of soil, the stronger the water-holding capacity of soil, the easier debris flow to occur. The internal mechanism of forming debris flows can be revealed deeply through above experiments; it also develops new ideas on debris flow forecasting.