Stability Analysis of a Tailings Dam-A Comparative Study

Tailings dams are used to impound waste tailings generated by the mining industry. The tailings material is fine-grinded particles of sizes similar to clay particles however they behave as cohesionless material. The tailings dam under consideration is a zoned dam raised in six stages using the centre line method and having three different types of fill materials. The zones, from upstream to down-stream, are consisted of (i) impervious material (ii) compacted tailings and (iii) pervious random fill. An inclined chimney drain and a connecting horizontal filter are provided to keep most of the dam section on the downstream side dry. The main objective of this study is to perform static and pseudo-static analyses by the Finite Element Method, using the Strength Reduction Technique, and comparing the results with those from various Limit Equilibrium Methods, such as Bishop Simplified, Janbu Simplified, Janbu Modified, Spencer, Corps of Engineers-1, Corps of Engineers-2, Lowe Karafiath and Morgenstern-Price for both circular and non-circular failure surfaces. The results are presented in the form of normalised plots considering the following cases: (i) Stagewise (Without Tailings) (ii) Stagewise (With Tailings) (iii) Considering circular failure surface, and (iv) Considering non-circular failure surface.