Role of the Single Sheet Pile Beneath the Dams on Seepage Parameters Maintenance: Review

Seepage is a significant issue that contributed to the dam’s failure. Different water levels on the U/S and D/S sides produce seepage and uplift pressure. This process displaces particles under the dam foundation, creating a seepage pathway and ultimately weakening the structure. This review paper focuses on identifying the optimal single-sheet pile technique for reducing seepage flow, uplift pressure head and controlling the exit gradient beneath the dams. Sheet pile walls are flexible, interlocking structures embedded in soil to resist horizontal pressure and accommodate significant deformations. Seepage in some Iraqi earth dams was concluded. The optimal situation for single sheet pile penetration, as one of the economic techniques, has been identified. The review results indicated that the best location for penetration of a single sheet pile is at the toe point, at an angle of 125° toward the upstream to mitigate seepage and 90° to 120° to provide the best exit gradient. However, the upstream heel sheet pile has been recommended to provide the lowest uplift pressure at an angle of 90° to 150° towards U/S.