Abstract With the deepening of mining,dynamic disasters,the range of disaster-related rock formation motion is beyond the traditional plane model. The movement of overlying strata spacial structure affects the distribution of mining stress field;and the stress distribution and stress concentration of the coal pillar caused by mining are the stress condition and primary cause for rockburst. Therefore,an analysis of the movement rules and mining stress field distribution of overlying strata and a study of the pressure source which acts on the coal pillar by the movement of the S-shaped overlying multi-strata spatial structure are the theoretical basis on the study of mechanical mechanism of rockburst caused by the coal pillar. The residual coal pillar of the 6th layer in Huafeng Coal Mine is taken as research object. The movement rules of overlying strata of the 6th layer and the S-shaped overlying multi-strata spatial structure of four the 4th layer are studied,and the pressure source during the movement of S-shaped overlying multi-strata spatial structure of coal pillar is analyzed. The stress field of coal pillar is also analyzed and the mechanical mechanism and stress condition of rockburst are studied through the stress computing and the microseismic monitoring. The study results indicate that the high stress caused by the coal mining of the 6th layer and the 4th layer is the key stress condition for the rock burst of coal pillars, and the fundamental inducing factor of the rock burst of the coal pillar is the difference of high stress which exist around the coal pillar. Based on the stress computing,pressure relief methods of coal pillar are discussed.
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Received: 01 March 2012
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