Abstract: At present,the domestic many using phase open stoping is made between flatback cut and fill stoping in mining of the mine,the traditional experience,highly generally within 60 m.Even if higher stages are adopted,such as the 120 m high stage,segmented rock drilling is adopted,that is,the rock drilling with large diameter and deep hole downward is completed in two sections,and the secondary drilling level is increased in the middle,which increases the production cost.Aiming at a new mine with a height of 60 m stage,the technical feasibility of mining with a height of 60 m stage to 90 m high stage was studied from three aspects of stope stability,backfill stability and drilling method selection by means of FLAC3D numerical analysis,Terzaghi calculation model and empirical formula.The results show that when the stope width is 15 m and the backfill strength is over 3.24 MPa (equipped with 1∶6),the drilling method of increasing the bottom drawing height can meet the production process and safety requirements of the stope at 90 m high stage.With the development of mining technology and equipment,it is expected that more and more mines will have the possibility of high stage mining in the future.

Key words: high phase,FLAC3D software,terzaghi model,stage open stoping