Study of The Bench Slope Stability By Numerical Method, Case of Ouenza Mine Algeria

Mine slope stability remains a key issue that arises when operating open pit deposits. Slope stability has a direct influence on work safety in the mine, technological operating principles, the total depth of mine drainage problems, etc. Too high slope angles can lead to destabilization, landslides development and flows over the edges of the mine. These accidents cause a lot of damage to businesses and hinder the normal cycle of operations, not to mention they can be dangerous to the lives of personnel. The definition of slope angles that ensure stable operations requires a detailed study of all geological and geotechnical factors of rock mass: lithology, tectonic conditions, physical and mechanical properties of rocks, discontinuities of the rock mass, the hydrogeological conditions, etc. To prevent slippage in the Ouenza mine, it was proposed to study the bench slope stability by numerical method based on finite elements (implemented in PLAXIS software). To better understand the bench slope stability problem, we modelled the mine bench slope to the study of the structure in two dimensions. For the calculation of the stability, plane strain assumption is adopted. The mechanical behaviour of rocks follows the Mohr-Coulomb criteria.