Mechanism of Downcutting Erosion of Debris Flow over a Movable Bed

作     者：Pan Hua-li Huang Jiang-cheng Ou Guo-qiang 

作者机构：Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and Environment CAS Asian International Rivers Center Yunnan University 

出 版 物：《Journal of Mountain Science》 (山地科学学报（英文）)

年 卷 期：2015年第12卷第1期

页      面：243-250页

核心收录：

学科分类：08[工学] 0837[工学-安全科学与工程] 

基　　金：supported by the National Natural Science Foundation of China (Grant Nos.50979103 and 40901007) 

主　　题：Debris flow Down cutting erosion Infinite slope theory Critical conditions Flumeexperiments 

摘      要：The phenomenon of debris flow is intermediate between mass movement and solid transport. Flows can be sudden, severe and destructive. Understanding debris flow erosion processes is the key to providing geomorphic explanations, but progress has been limited because the physical-mechanical properties, movement laws and erosion characteristics are different from those of sediment-laden flow. Using infinite slope theory, this research examines the process and mechanism of downcutting erosion over a moveable bed in a viscous debris flow gully. It focuses specifically on the scour depth and the critical slope for viscous debris flow,and formulas for both calculations are *** scour depth and the critical conditions of downcutting erosion are related to debris flow properties(sand volume concentration and flow depth) and gully properties(longitudinal slope,viscous and internal friction angle of gully materials,and coefficient of kinetic friction). In addition, a series of flume experiments was carried out to characterize the scouring process of debris flows with different properties. The calculated values agreed well with the experimental data. These theoretical formulas are reasonable, and using infinite slope theory to analyze down cutting erosion from viscous debris flow is feasible.