Approach to the erosion threshold of cohesive sediments

Erosion of cohesive soils is represented typically as an erosion threshold or erosion rate. Predicting the erosion threshold of the cohesive soils requires taking into account cohesion, which results from interactions between clay particles. Beyond the usual dependence on grain size, a significant correlation between erosion threshold and porosity or density measurements is confirmed for the cohesive soils. Correlations of the erosion threshold to the solid volume fraction and effective density of cohesive soils are proposed based on the fractal model for cohesive aggregates. Cohesion forces, the long-range van der Waals interaction between two particles is taken as the resource of the erosion threshold. The model verification is conducted by comparison with experiments of the erosion thresholds published in literature. The results show the proposed model for the erosion threshold offers good agreement with experimental data.