Cover structure optimization study on open-pit to underground mining

Combining actual situation of Open-pit to underground mining in Xingshan Iron Mine, the main mining technical and economic indicators of the different thickness and composition of particle sizes were calculated by PFC numerical simulation software. The displacement and velocity of different size particles in the process of mining were researched, and the optimization cover structure is put forward which is of great significance to the improvement of the technical and economic indicators of the mine.