Study On Appraisal Of Rockburst Hazard In Isolated Coal Pillar

By adopting the method of the research in laboratory, this paper makes original attribute and the Mechanical conditions of which are all about rockburst caused by impact trend of isolated seam, sets up a model about rockburst of isolated coal pillar, and analyzes isolated coal pillar's all kinds of means of destruction in detail under different Mechanical conditions. According to the features appearing in rock-burst, this article analyzes the reasons affecting isolated coal pillar of rock-burst on all sides. By applying the theory of underground pressure, this paper calculates the stress distribution of coal pillar's roof and floor. On the basis of different stress's characters of coal pillar belonging to different widths, this paper makes three rules of stress distribution of isolated coal pillar: general stress distribution saddle-type stress distribution and arch-type stress distribution. Conducted the simulator study using RFPA software to the different widths coal pillar. Combining holding theory, acoustic emission and damage mechanics relations, this paper analyzes destruction mechanism of different widths coal pillar and influences of the heterogeneity to the destruction of coal, has confirmed the law of isolated coal pillar's stress distribution. Based on the law of isolated coal pillar's stress distribution, making combination between holing theory and numerical simulation, by using revision index of range target, and by referring to plane of weakness slipping ,crush of coal pillar and impact of floor impact of coal pillar and floor, puts forward the detail classification to evaluate impacting hazard of isolated coal pillar, and target of evaluation of each method of evaluation. Finally, this paper has carried on the risk analysis and evaluates in view of the exploiting conditions of 43 ±05 isolated working face in dong tang mine, providing the theory basis for evaluation about the hazard of the isolated coal pillar's rock-burst, and purifying the theory and method of evaluation of the hazard of isolated coal pillar's rockburst.