Experimental Study on Suffusion of Gravelly Soil

摘要

Although internal erosion causes serious hazards to embankments and dams, studies on the emission of fine soil particles and the development of non-uniform penetration of the soil foundation after suffusion do not go far enough. Given that suffusion development is random and complex, this study employed self-designed equipment to conduct tests under specific conditions. Twelve samples with three different pore size distributions were used to make a comparative analysis on aspects such as piezometric head, flow rate, coefficient of permeability, trend of fine particles, and accumulated sand emissions. Furthermore, the coefficient of permeability, void ratio, movement trend of fine particles in samples, and changes in content of the remaining fine particles were studied. Combined with theoretical calculations, correlations among the movement trend of fine particles in the samples, content of remaining fine particles and uneven changes in the permeability coefficient were shown. Using the relationship between permeability and porosity, we derived a theoretical formula was deduced from the changing amount of accumulated sand emissions over time under fixed upstream total head.