Abstract
Water-retaining structures, such as earth dams, require a careful assessment of seepage behavior to ensure structural stability and prevent failure. This study presents a comprehensive numerical investigation of sheet pile cutoff walls as seepage control measures in earth dam foundations using finite element analysis with SEEP/W software. An earth dam model with varying sheet pile configurations was analyzed to evaluate the effects of sheet pile position and length on seepage parameters, including flow rate, water pressure head, and hydraulic gradient. Four different sheet pile lengths (6, 8, 10, and 12 m) were positioned at various distances from the dam heel (25.5, 51, 77, and 102.5 m) to assess optimal placement strategies. Results demonstrate that sheet piles significantly reduce seepage in all scenarios of the research. Sheet piles positioned closer to the downstream toe achieved superior seepage control performance compared to those at upstream positions. Increasing sheet pile length results in a substantial rise in water pressure head loss and hydraulic gradient by about 13 and 15%, respectively, whereas seepage discharge diminishes (about 9%). Moreover, it was deduced that the sheet pile length has a higher impact on changes in the studied parameters and earth dam safety compared to sheet pile distance.