Abstract: For lean ores above 1 250 m level in Jinchuan No.2 Minefield, the optimization design and numerical analysis of excavating-filling engineering were studied.According to the practical excavating-filling projects, 9 project schemes were presented and the numerical analysis on each scheme is made by FLAC2D from the effect of each scheme on the stability, surface subsidence, displacements of lean ore roof and shaft of stope.Then an optimal one is determined.The optimal project and practical excavating-filling project were analyzed by the numerical analysis.The comparison of this result indicated the effect of lean ore mining on the surface subsidence, stress and shaft.

Key words: Excavating-filling, FLAC, Optimization design, Numerical analysis