Application of the deterministic block theory to the slope stability design of an open-pit mine in Morocco

Purpose. Discontinuities in rock masses are natural fractures that delimit various block shapes and sizes, which can fall, slide or topple from the excavation collapse under their own weight inducing probably severe damage. Thus, it is essential to carry out a analysis before beginning any surface underground project. This paper proposes methodology based on key theory select suitable slope of different discontinuous an open-pit mine Morocco. Methods. At first, main discontinuities each bench determined projected onto stereonet with maximum dip angle plane. Then, possible identify removable blocks by using theorem removability according theory. After that, limit equilibrium performed determine failure mode friction required stabilize blocks. When selected plane found be unsuitable, changed reduced one degree, same approach repeated until safe obtained. Findings. The results proposed have shown angles studied benches range 63-73°. compared used mine, between 58-78°, this study close in-situ conditions. Originality. In research, fractured was optimized eliminating unstable (key blocks) stereographic projection method Practical implications. Using methodology, stability slopes civil mining-engineering projects designed assessed when geotechnical data very limited.