Por: Jose Luis Ramírez, GeoRam SRL.

Abstract

The study evaluates the stability of mining tailings dams in Peru, highlighting the frequent use of traditional limit equilibrium methods (LEM) in stability analysis despite the limitations recognized in Peruvian regulations. This points out the complexity of the stability analysis of tailings dams, which requires exploring several failure mechanisms, adding uncertainty to the safety assessment process. 

The stability evaluation will be carried out by means of the Shear Strength Reduction Method (SRM), which serves as a numerical alternative that considers material constitutive models supported by finite element methods (FEM). The use of these methods was carried out in 8 tailings dams made of different soil and rock materials, distributed in different mining units in Peru. 

The use of numerical methods can have the following advantages, because isotropic, transversely isotropic, orthotropic and even nonlinear deformational models can be incorporated, which allows a more rigorous adaptation to the behavior of the materials present in the mining dam. In addition, representations of the maximum shear deformations can be obtained, which will be indicative of the failure mechanism that may occur in that component.

The software used for the simulations and static load calculations were Slide® for the LEM and RS2® for the FEM used to determine the safety factors of the different tailings dams.

The article proposes the use of numerical methods in the analysis of the physical stability of tailings dams and the comparison of safety factors (SF) and the shear reduction factor (SRF) between the LEM and FEM methods. For the validation of this comparison, statistical methods were applied and the results obtained using the statistical technique of hypothesis testing, validating the null hypothesis that indicates that the SF and SRF for both methods by LEM and FEM respectively are equivalent and that there are no significant differences.