Investigating concentrated leak erosion behaviour of cohesive soils by performing hole erosion tests

摘要

Internal erosion by piping is one of the common causes of failure of embankment dams and dykes. This phenomenon occurs when preferential flow paths develop in the earthfill or foundation; through these water flows, carrying away particles of soil and leading to the formation and the evolution of a continuous 'pipe' between the upstream and the downstream side. A series of hole erosion tests were conducted on cohesive soils in order to quantify critical shear stress and the coefficient of erosion: white kaolinite, proclay kaolinite and a hostun sand/proclay kaolinite mixture. The effects of compaction energy, moisture content, degree of saturation and the percentage of fines were investigated. The experimental results show that these parameters play a key role in the erosion characteristics.