Abstract: According to the actual geological conditions of of 1412(1) fully mechanized face of Dingji mine, the control mechanism for surrounding rock deformation of roadway driving along goaf is analyzed in detail, the numerical computation model of reasonable coal pillar of island coal face in deep well under the conditions of mining dynamic pressure is established. The surrounding rock stress distribution of overlaying strata stable stage and dynamic pressure stage, and the plastic zone distribution of coal pillar and roadway surrounding rock with the coal pillar width is 6,8,10 m are discussed. It is concluded that, the minimum values of stress peak and stress concentration factors under the conditions of the coal pillar width is 6 m.

Key words: Dynamic pressure, Deep well, Island coal face, Reasonable coal pillar width