Effect of spatial variability of foliation orientation on mining slope design

ABSTRACT: Local variation in the foliated nature of the rock mass can have a significant effect on mining slope design, and it is often difficult to predict. This issue should be considered in pit design and continuously monitored during mine development. This paper describes the huge challenge of building the final southeastern wall of the Z pit pushback by mitigating the risk of slope failure caused by the spatial variability of the foliation orientation, knowing that previous mining in this sector of the pit had caused a multi-bench failure 125 m high and 200 m wide. The methodology based mainly on bench face cleanup, design compliance analysis, televiewer surveys, the modification of the blasting techniques and radar monitoring, made it possible to achieve optimal slope and to continue mining safely.