Author(s): H. D. To; A. Scheuermann; C. T. Nguyen
Linked Author(s): Canh Thai Nguyen
Keywords: Suffusion; Self-filtration; Internal stability; Constriction size distribution; Primary fabric
Abstract: Suffusion is a major reason, related to nearly half of dysfunction of dams and embankments. The suffusion starts when fine soil particles are mobilised and transported through constriction formed by the primary fabric. This transport leads to an increase of soil porosity and, thereby, a stronger seepage flow. When the flow is strong enough, the primary fabric might collapse and be restructured at the micro scale. This deformation can be accumulated and, then, lead to the internal erosion at the macro scale. Therefore, the suffusion assessment is of vital importance in risk assessments for hydraulic constructions. Many recent suffusion assessment methods assumed that there is a sharp boundary in soil particle size distribution, which divided it into two parts: primary fabric and transportable particles. This paper represents a new assessing method, developed on a recent numerical approach that there is a transitional zone between primary fabric and transportable particles in the particle size distribution of soils. The new method correlates the particle size distribution of the transportable fraction and the constriction size distribution constriction size distribution formed by the primary fabric. The constriction size distribution is calculated by a probabilistic method. The application of the new assessing method on experimental data shows good, coherent results.
Year: 2014