Research On Relationship Between The Energy Characteristics Of Coal-rock Mass And Intensity Of Rockburst

Rockburst is a dynamic disaster caused by external disturbance,such as coal mining,under the geological dynamic condition and accompanied by sudden release and dissipation of energy.Due to the difference of energy accumulation,release and dissipation during the process of rockburst,the strength of rockburst is different which posed a serious threat to the safety and efficient production of coal mines.It is not possible to determine the quantitative relationship between time and space in the prevention and control of rockburst.Therefore,the energy source of rockburst is analyzed,and the relationship between energy characteristics of coal and rock and the strength of rockburst are studied.The effect of borehole has been monitored.These results can provide a theoretical guidance for rockburst prediction and prevention.This paper studied rockburst from the view of energy inoculation,transformation and the performance form of coal-rock mass,and analysis the relationship between the energy of coal-rock mass and the strength of rockburst.Based on the characteristics of rockburst formation,the destruction energy density method of coal-rock mass is put forward to determine the critical energy condition of rockburst from the view point of self destruction and energy consumption of coal-rock mass.The energy sources of rockburst were determined by studying the regional geological structure characteristics.Muchengjian coal mine was divided I to V of active fault by using geo-dynamic zoning method.The control effect of active fault on rockburst was found out and the geological model of actual relationship between faults and mine engineering was established.According to the law of energy density distribution of the undisturbed rock mass,the energy condition of rockburst was determined,and the relationship between the energy density of coal seam 3~#and coal seam 2~#and the intensity of rockburst in Muchengjian coal mine was studied.The influence of mining induced stress on energy was studied under the condition of the undisturbed rock mass energy.According to the critical energy condition of rockburst,the energy density distribution in the mining process was studied,and the relationship between mining energy density and the strength of rockburst was determined.The relationship between coal and rock energy characteristics and the impact of in-situ stress,and the prevention and control measures of different types of rockburst was applied in Muchengjian coal mine.BOTDR distributed optical fiber sensing technology was first used to monitor the yielded zone range,the time and pressure relief effect in the coal seam.The strain value and yielded zone range around the pressure relief holes of different diameters and different holes were obtained.By this,we determined the reasonable drilling parameters and the advanced drilling time of borehole which can optimize the technical drilling parameters of pressure relief holes.The paper expects to further understanding the energy inoculation,transformation and development process of rockburst.At the same time,a new idea of grade prevention and control of rockburst disaster is opened,which provides reference and guidance for similar conditions of mine production.