Quartic Polynomial Packing Model for Sand-Fines Mixtures

Abstract

The addition of fines to sand directly changes the void ratio of a sand-fines mixture and thereby leads to a change in its mechanical properties. Numerous packing models have been proposed to capture the variation of limit void ratios with respect to the fines content. However, most existing packing models can hardly balance the precise predictions and the physical meaning at the specific boundary conditions. Accordingly, we established a new quartic packing model in this study to effectively exhibit the relationship between the limit void ratios and the fines content by volume for three representative cases. Five coefficients in this proposed model could be exactly acquired from the five boundary conditions. We proposed a reasonable procedure to determine the optimum value of the threshold fines content within the effective region derived from the upper limit line and two lower limit lines. Furthermore, the performance of the new quartic packing model was validated by various types of sand-fines mixtures.