Abstract:
Coal pillars in overlying coal seam with close distance can lead to the stress concentration and rock burst of lower coal seam. In order to figure out the stress distribution of floor and the damage characteristics of floor rock stratum, a three-dimensional numerical simulation method was applied in the study process. The study shows that the shape reflected in the simulation of coal pillar floor stress is like "inverted bell" when the width of coal pillar is less than or equal to 50 m; in other conditions, the shape is like "inverted tower". A power function relationship between maximum concentration stress of coal pillar center and coal pillar width, and with the increase of the width of coal pillar, the attenuation of coal pillars in the floor of stress concentration decreases gradually. The relationship of the maximum stress concentration factor of 3
#coal seam under overlying coal pillar center and the width of coal pillar is a negative exponent function. The relationship of coal pillar failure range and the width of coal pillar is a negative exponent function; most of the damage in coal pillar rock stratum is shear failure. Based on the influence of overlying coal pillar, rock burst zones of the sixth mine section 3
# coal seam working face were divided, and corresponding prevention and control techniques were proposed.