Numerical investigation of the influence of the combined seepage reduction scenarios on the hydraulic performance of the Alborz dam body

Seepage is a crucial factor in the design of dams as it can lead to failure if not controlled. This study delves into the numerical modeling of seepage and investigates the effects of different sealing systems on the foundation and body of earthen dams under steady flow conditions. The study explores various sealing conditions ranging from optimal to critical, which include clay blankets, drains, and clay curtains in the foundation. In general, the combined effects have been studied by combining all types of defined elements without considering their geometric dimensions. The study reveals that the different seepage reduction systems have significant effects on reducing the flow within the dam body and foundation. The trend of seepage discharge increases with height and reaches a maximum between 38 to 46 meters before decreasing again. The combination of a drain, clay blanket, and clay curtain proved to be the most effective in ensuring the dam's stability. The study shows that this combination can reduce the flow rate by an average of 83%, the seepage rate by an average of 15.5%, and the water head by an average of 9.5% at downstream of the dam. The results of this study suggest that the diversity in the type of flow seepage reduction systems has a significant effect on reducing the flow inside the dam body and foundation. This finding underscores the importance of considering the combined effects of different sealing systems to ensure the stability of the dam.