Abstract: In order to discuss the mechanics of pillars in discontinuous goafs,FLAC3D numerical simulation technology is used to analyze the stress state of the ore pillar in the discontinuous goaf formed by the horizontal slicing and filling mining method.The research shows that the force of the ore pillar in the discontinuous goaf is mainly affected by the dead weight stress of overburden,and the horizontal stress has little influence on it.And with the increase of the buried depth,the vertical force on the pillar increases approximately in a straight line.As the span of discontinuous goaf increases (the number of approaches increases),the stress in the vertical direction of discontinuous goaf gradually transits from both sides of surrounding rock to the middle of ore pillars.

Key words: Discontinuous Goaf, FLAC3D numerical simulation, Stress state of the ore pillar