Modeling of soil migration phenomena in embankment dams

The problems of granulometric stability related to particle migration phenomena (i) at the contact between materials affected by different grain size or (ii) through widely or gap graded soils (i.e. suffusion) are well recognized, as shown by several historical dams incidents. For a complete simulation of these phenomena and their evolution towards possible limit conditions (i.e. clogging, blinding, complete erosion), the (space and time) variability of soils granulometric properties (i.e. voids volume, porosity, permeability, flow velocity, local piezometric gradients, flow direction,…), as well as the particles erodibility and deposition, must be taken into account. The available empirical and analytical (derived from “continuum” mechanics) methods to analyze particle migration phenomena generally don’t considerer the coupled effects of these micro-structural (at the grain scale), meso-structural (porosity, permeability) and hydraulic variables. Thus, a numerical procedure allowing to simulate coupled 1D seepage and particle migration processes, by taking into account the mutual dependency of the above cited governing variables, has been developed and applied to carry out detailed analyses and review of available, selected experimental data.