Mercier, F., Bonelli, S., Golay, F. et al. Acta Geotech. (2015) 10: 319. doi:10.1007/s11440-014-0349-5
This study focuses on the numerical modelling of the concentrated leak erosion of a cohesive soil by turbulent flow in axisymmetrical geometry, using the Hole Erosion Test (HET). The numerical model is based on the adaptive remeshing of the water/soil interface to ensure the accurate description of the mechanical phenomena occurring near the soil/water interface. The erosion law governing the interface motion is based on two erosion parameters: critical shear stress and the erosion coefficient. The model is first validated in the case of 2D piping erosion caused by laminar flow. Then, the numerical results are compared with the interpretation model of the HET. Three HETs performed on different soils are modelled with rather good accuracy. Lastly, a parametric analysis of the influence of the erosion parameters on erosion kinetics and the evolution of the channel diameter is performed. Finally, after this validation by comparison with both the experimental results and the interpretation of Bonelli et al. , our model is now able to accurately reproduce the erosion of a cohesive soil by a concentrated leak. It also provides a detailed description of all the averaged hydrodynamic flow quantities. This detailed description is essential in order to achieve better understanding of erosion processes.