Abstract: The two-stage underground mining of Jiama Copper Polymetallic Mine adopts the large diameter deep hole stage mining method with subsequent backfilling. In order to effectively control the ground pressure disaster and realize the safe and efficient mining of the ore body， the stability of the roof and pillar of the stope is synthetically studied by a variety of methods including the theoretical calculation， Mathews stability map and FLAC3D numerical simulation. On this basis， the reasonable structure parameters of the stope are determined. The results show that the width of 12 m， 15 m and 18 m can meet the requirements of pillar stability. When the width of the stope is 18 m， the maximum allowable stope length is 77.3 m. When the length of the stope is 60 m， the maximum allowable width of the stope is 22.4 m. Considering the stability of the stope and the deep high stress environment， 15 m is more suitable for the width of the Jiama Copper Polymetallic Mine， and the stope structure parameters are recommended as 15 m×60 m.

Key words: Mathews method, Numerical simulation, Stope stability, Structural parameters