Permeability, Erosion Resistance and Filters of Broadly Graded Gravelly Soil for Embankment Dam Construction

In connection with the construction of Pubugou Project, anti-seepage behavior and piping resistance of gravelly soil with broad gradation were studied systematically and the criteria of critical filter for resisting erosion failure of gravelly soil were proposed. Results showed that gravelly soil will fulfill impermeability requirement when P_&lt;0.1 of fine particle content >25% and the effect of impermeability will be more remarkable when filled with 2%³% on the wet side of optimum water content; the criteria of critical filter for preventing core material from erosion failure are D15≤1.1mm, D₁5/d₈5⁴≤15¹7 when P_&lt;0.1<30%,andD₁5≤1.1mm, D₁5/d₈5⁴≤20 when P₀.1>30%.