基底刮铲效应对岩石碎屑流停积过程的影响

岩石碎屑流在运移停积过程中，对运移路径存在强烈的刮铲效应。首先分析总结了碎屑流基底刮铲效应的特征，然后采用二维颗粒离散元模拟方法模拟岩石碎屑流水平基底上刮铲。模拟试验证明了基底刮铲效应可以增强岩石碎屑流在水平面上的运移停积能力。通过进一步研究水平基底物理力学性质和分层情况对刮铲效应和岩石碎屑流运移过程的影响，证明了减小基底物质的强度会增强刮铲效应，但基底表层松散堆积物质低密度、低强度的特点才是影响岩石碎屑流最大运移堆积距离的关键因素，并具有类似润滑剂的特性；相对地，基底底层高强度、高密度物质的强度变化对最大运移距离影响很小。

Influence of substrate ploughing and erosion effect on process of rock avalanche

The substrate of rock avalanche bears severe ploughing and erosion effect during the depositing process of rock avalanche.Firstly,characteristics of the substrate-ploughing and esrosion are described and compared with each other.Then the calibration and verification of particle flow method are carried out,and multiple numerical rock avalanche depositing tests based on this method are done.Test results reveal that both the substrate ploughing and esrosion effect can enhance the runout ability of rock avalanche moving on a horizontal substrate.The influence of substrate materials are also studied by doing numerical tests.The results indicate that smaller strength of the substrate materials leads to more intensive ploughing and erosion effect,however,it seems that,the characterstic of lower strength and lower density of the substrate’s surface material is the key factor of enlarging the runout ability of rock avalanche,this fragile layer serves as lubricant in the base;in contrast,the strength of the underlying substrate material gives no contribution on the avalanche’s runout ability.