🏘️ Polder Dyke: Dupuit Seepage Line, Under-Seepage and Piping Creep Path (2D)

Cross-section of an earth dyke between a high river and a low polder, with the water line inside the dyke body, a sand layer under it and an optional sheet pile. Set the river and ditch levels, the dyke height, crest width and slopes, the permeability of the dyke and of the sand, the thickness of the sand and the depth of the sheet pile, and see the seepage through and under the dyke, the Lane creep path against the path the soil requires and the shortest sheet pile that makes the dyke safe against piping. The Dupuit line, the continuity of the flow, a relaxation solution under the dyke and the creep path are checked numerically, with four in-page numerical checks.