| Practical case show that dynamic disasters have mutual features of coal-gas outburst and shock burst in deep high methane mine. So how to define and prevent these disasters is a problem. In order to meet practical demand, a new classification will be built to substitute the dated system and induction and transforming conditions between disasterswill be studied based on the further studied on united the coal-gas outburst and shock burst. So relyed on the National Great Research Foundation of China(973 Programs)"Mechanism of coal and rock , gas dynamic disastrous evolution"and the National Natural Science Foundation of China"the fundamental study on Mechanism and Prediction & Prevention techniques of Coal-gas Outburst", the thesis give a study on the a new classification and induction and transforming conditions about rockburst and coal-gas outburst in the following aspects:(1)Properties of coal fedding from the coal seam where happening atypical dynamic disasters are different from the coal fedding from the coal seam where happening typical dynamic disasters.So utilizeing the gas sealing system,analogic uniaxial experiment method was proposed.Mechanical Properties and Response of Coal treated with gas under effective confirming pressure=0 had been studied also.(2)In viewing the high temperature, pore-pressure, stress in deep mining conditongs, the variation has been studied of which instantaneous desorption characteristics and permeability of gas under different confining pressure, temperature and pore-pressure. Also the effect of stress,gas and temperature on disasters have been researed.(3)The failure of coal caused by accumulation of damage and development of fracture. So the evolution laws and failure characteristics of fracture have been studied.Two main forms of failure are completely analyzed by theoretical analysis and numerical simulation that are shearing rheological failure affected by quasi-static loading and tensile instantaneous failure for dynamic loading. The force analysis models are established respectively.(4)Energy transformation is the essential character of material'physical process. Material damage is one of failure phenomenon caused by energy. The essence of dynamic disasters is the result of energy dissipation and release. Unified energy equation has been built based on the analysis about energy source and occurring essence of disasters. Energy transfer process is analyzed and energy criteria is put forward in the paper.(5)A new classification has been built based on the unified energy equation and the amount of participation by gas which contains typical disasters (rock burst and coal-gas outburst) and atypical disasters( extrusion of coal-gas and impact of coal-gas), Distingish methed of Atypical dynamic disasters has been proposed. The experimental results show that this distingish methed is scientific and feasible .(6)Based on the analysis of the similarities and differences of coal-gas outburst and rockburst , unified theory and induced transformation mechanism has been proposed at different stages. Control action of stress affecting on disasters is analyzed and the resbectively characters of disasters occurring in stope and roadway is also studied.(7)The maximum drillings volume commonly used just reflects the stress of one point, but the stress gradient is the main causes of disasters occurred. So the Index of drillings incremental volume is put forward for completely reflect the change of stress. The stress change of inflection points are the key of study. Theory analysis and practice proved, the index of drillings incremental volume plus the maximum drillings volume can completely reflect the stress change in working face, so the occurrence of disaster can be predicted more accurately.
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