DIYALA JOURNAL OF ENGINEERING SCIENCES

Abstract

The study of slope stability is important in the design and construction of the earth dams under influence of earthquake and some surcharge loads. Some factors affect the slope stability for the earth dam such as change the water level in the reservoir or rapid drawdown of the water level. In the present study, limit equilibrium methods and finite element method have been used to calculate the factor of safety of earth dam. The main objective is studying the influence the soil strength parameters including cohesion, angle of internal friction and unit weight of soil on the values of factor of safety of the upstream slope for earth dam. The results show that the values of factor of safety increase when the values of soil strength parameters (cohesion, angle of internal friction)and water level increased, and the value of unit weight of the soil decrease, and the values of factor of safety, decreasing fast in rapid draw down of the water level. The main conclusion is the stability of the earth dam increases when the soil strength parameters (cohesion, angle of internal friction) increase and unit weight of the soil decrease with increasing the water level in the reservoir and the earth dam may be exposed to the collapse in the case of the rapid drawdown of water level.