Abstract: In view of the fact that Chengjiagou Iron Mine utilizes its discarded open pit for tailings deposit, simulation study is made on the stability of underground stope when the open pit is used for tailings deposit by ANSYS 3D finite element numerical simulation method based on the analysis of the mine engineering geological, hydrogeological and ore-rock physical mechanic parameters and in light of the mine reality. As a result, the appropriate tailing heap height and underground stope structural parameters are determined and specific engineering control measures are proposed for potential problems.

Key words: Tailing discharge into open pit, Stop structural parameters, 3D numerical simulation, Engineering control measures