Evaluation of Stability of Embankment Dam by Limit Equilibrium and Numerical Analyses Methods: Example of a Waste Dam in Turkey

In this study, stability of a lifetime ended old waste clay fill dam body was evaluated after increasing the dam height of 3 meters using limit equilibrium and numerical analyses. In the limit equilibrium analyses, stability of the old waste dam was evaluated by Bishop Method considering the effect of silting and the seismic loads and the factor of safety determined as 2.167. Afterwards, stability of the dam which increased body height of 3m was evaluated in four stages using the limit equilibrium analyses. In the first stage, stability analysis for condition after construction was realized without siltation and seismic loads using and the factor of safety was found as 2.171. In other stages, stability analyses were conducted considering effect of the silting load and both seismic and silting loads. The factors of safety were determined as 1.946 and 1.443, respectively. Similarly, stability of new dam body was analyzed without siltation and seismic loads using shear strength reduction method (FE-SSR) and the factor of safety was found 2.16. In the stability analyses by considering siltation load and both siltation and seismic load, the factors of safety were determined as 1.97 and 1.23, respectively. The results obtained from stability analyses show that the factor of safety values is higher than 1.2 which is the lower limit for earth dams and no stability problem is expected after increasing the dam height