Slope Stability in a Mining Environment M'haoudatt-Zouerate Site, Mauritania

Abstract

The instability of the M'HAOUDATT pit is a major problem often encountered on the wall composed of a network of fractures located in unfavorable conditions for a very soft geological formation. Therefore, the trend in large open-pit mines is to use high-energy blasting to increase conveying performance and crusher throughput. The increase in blasting energy concentration can threaten the integrity of the pit wall. In this paper, we aim to find a suitable plan to stabilize the pit deposit, through analyses of structural and lithological data on the pit walls, with an interpretation of the lateral and depth extensions according to the geological complexity of the deposit. Followed by an analytical treatment of the current pit parameters. Data processing included core classification, kinematic assessment of failure mechanisms based on visual observations on the exposed faces of the expected pit. The results of the laboratory tests were also used to define the rock mass parameters used to establish a stable slope design. The analyses showed the need for an effective strategy to ensure that the slopes won’t be damaged by blasting. This wall control strategy aims to produce a fragmented bulk ore pile and a slope as designed and in good condition. A good understanding of the failure mechanisms is necessary to ensure better monitoring of the rock slopes of the M'HAOUDATT pit.