The phreatic surface and exit point of seepage flow through horizontal embankment dams

The development and validation of an analytical solution for the flow through horizontal embankment dams was proposed in this study, and the analytical solution is in fair agreement with experimental data. Under the condition of negligible downstream depth, the parameter, β, shown in the analytical solution increases with the increasing ratio of embankment-dam width to upstream depth. The Hele-Shaw model is employed to examine the phreatic (free) surface and exit point of seepage flow by adjusting gap width and fluids density. Aluminum powders were used to as tracking particles inside the gap and the flow visualization was performed. The phreatic surfaces and exit points are in good agreement between experimental data and the analytical solution. The assumption of a parabolic piezometric head was verifiedby experimental data. When the ratio of down-upstream water depth is large than 0.9 or the ratio of upstream depth-width is less than 0.1, the solution based on Dupuit model is close to the analytical solution. This model has the advantage to predict the seepage point for understanding the seepage-induced sloping failure.