Back-analysis study on slope instability in an open pit mine (Algeria)

• Published in: Natsional'nyi Hirnychyi Universytet. Naukovyi Visnyk no. 2; pp. 24 - 29
• Main Authors: Fredj, M, Hafsaoui, A, Riheb, H, Boukarm, R, Saadoun, A
• Format: Journal Article
• Language: English
• Published: Dnipropetrosk State Higher Educational Institution "National Mining University" 2020
• Subjects: Catastrophic failure analysis; Equilibrium methods; Failure mechanisms; Finite difference method; Finite element analysis; Finite element method; Geotechnical engineering; Mathematical analysis; Mechanical properties; Methods; Mines; Mining; Mining engineering; Numerical analysis; Open pit mining; Parameters; Sensitivity analysis; Shear strength; Sliding; Slip; Slope stability; Software; Stability analysis; Algeria
• ISSN: 2071-2227; 2223-2362
• DOI: 10.33271/nvngu/2020-2/024

Purpose. To analyze the sliding from the geotechnical point of view and to identify the plausible causes that influence it.Methodology. To analyze the sliding from the geotechnical point of view and to identify the plausible causes that influence it, our study follows the following chronological order. Firstly, a feedback reconstructs the slip from the geotechnical point of view; a back-analysis is required to confirm the surface failure. Next, a check will be made of the surface failure through the finite difference method and using the shear strength reduction by finite difference method (SSR-FD). A parametric study on the influence of the geometric parameters is performed to see the influence of the latter on the stability. The plausible cause that has directly influenced this sliding is shown.Findings. This paper considers the application of three methods: limit equilibrium method (LEM), finite element method (FEM) and finite difference method (FDM) to perform back analysis and find out the layer of slope failure in an open pit mine.Originality. Three different approaches LEM, FEM and FDM were used to perform the back-analysis the rock mass properties and to investigate the slope failure mechanism and the accuracy of this method in mining engineering field.Practical value. This study has illustrated that non-compliance with the art, open pit mining standards and early planning of the mining method can most often lead to critical situations and catastrophic results. The back analysis of the slip site allowed us to reconstruct the break already observed and to draw maximum lessons on the mode, location and mechanical parameters that triggered this break.