As one of the dynamic disasters of coal mines,rockburst seriously affects underground safe coal mining.Based on the laboratory test,field test,and theoretical analysis,this study proposed the principle of the rock burst induced by the combination of dynamic and static stresses and divided such rock burst into three types,including induced by primary dynamic stress,mainly induced by dynamic stress,and by dynamic stress in low critical stress state.The expressions of the static stress induced by coal mining and dynamic stress induced by mining tremors were obtained.Moreover,theories and technologies at home and abroad were summarized concerning the monitoring,forecasting,and preventing of rockburst.These mainly include the zoning and leveling forecasting method,electromagnetic radiation technology,elastic wave and seismic wave computed tomography technologies in aspect of rockburst monitoring,as well as the intensity weakening theory,the strong-soft-strong structure effect,the directional hydraulic fracturing technology,the roadway support system in regards of rockburst prevention.The prospect of rockburst development suggested that researches concerning the rockburst mechanism should be quantitatively developed around the roadway and coalface surrounding coal-rock mass.It should be focused on the rockburst mechanism and prevention technology of mining with over 1,000 km deep and mining in large tectonic zone.In addition,the monitoring and prevention of rockburst should be based on rockburst mechanism.
Linming DouZonglong MuZhenlei LiAnye CaoSiyuan Gong
Spatial structure of overlying strata existed and evolved dynamically with the exploitation scope （boundary conditions） changes in coal mines and to induce rockburst. Based on the“key strata”theory, the integrated spatial structure of overlying strata was put forward, which was composed of “O-X” structure in the plane section and “F” structure in the vertical section. The formation and ongoing instability of the“O-X”and“F”structures were called as dynamic evolution cycle of the overlying strata. Three basic categories of “O-X”, “F” and “T” structures were defined, and the strata behaviors of each spatial structure were analyzed. According to energy theory, mechanism of rockburst induced by spatial structure instability was discussed. The research expanded the scope of traditional ground pressure theory and provided a guide for the prevention of rockburst and mining tremors induced by structure instability of overlying
