Slope Stability Analysis of Zoned Earth Dam with RCC Overtopping Protection

Roller Compacted Concrete (RCC) has become a popular method for providing spillway and overtopping protection for earthen dams. So far, some studies were performed on the effects of RCC protection against hydraulic forces and erosion. The purpose of the present numerical investigation is to study the effect of interaction between downstream RCC spillway and embankment dam during steady-state seepage flow and overtopping over spillway. For this purpose, a zoned embankment dam with broad-crested spillway on its downstream slope is modeled using finite element numerical modeling. The results show that interaction between the dam body and RCC spillway ends up with increasing the factor of safety (FOS) of downstream slope during steady-state seepage. This factor does not decrease during overtopping conditions.