Evaluation of Tailings Dam Slope Stability Using Cement-Treated Soil with Duraflex Addition

Abstract

Slope stability in tailings dams represents a critical challenge in the mining industry due to the potential impacts of failure. This research evaluates the effectiveness of the soil-cement technique with the addition of Duraflex for slope stabilization in dams constructed with borrow material. Geotechnical parameters were determined for representative tailings mixtures (fine sand and clay in 50/50 and 75/25 ratios), treated with 10 % Type I Portland cement by soil weight and the addition of Duraflex at 2 % by cement weight. Grain size analysis, Standard Proctor, direct shear, and unconfined compressive strength tests were conducted at 7 and 28 days. Stability analyses were performed on a realistic dam section using the limit equilibrium methodology (Spencer's method) under static and pseudo-static conditions. Results showed that the natural soil presented a static Factor of Safety (FoS) of 1.48, while soil-cement improvement increased FoS values above 2.00. The addition of Duraflex improved initial strength, particularly at 7 days. A brittle behavior was observed in the cemented mixtures; however, pseudo-static FoS values exceeded 3.00, confirming the technical effectiveness of the proposal.