Abstract: The mining process of -170 m middle section was simulated by FLAC^3D, and it calculated the stress and strain of the ore pillars and roof, and the subsidence of open slope. In the process of simulation, the stability of the ore block was analyzed by tailing after the displacement of roof midpoint and the max unbalance force. The numerical results show that the displacement of the ore midpoint is in allowing range and the max unbalance force ultimately tends to 0, which verifies that the method of drift cut-and-fill stoping is safe and the best mining sequence is determined. It brings a simple and efficient technical support to recover hanging-wall ore safely on complicated geological condition, while protecting the village and farmland.

Key words: Numerical simulation, Stability, Slope, Mining subsidence