| In accordance with the form and source of loading, rockburst can be divided intostatic-loading rockburst and dynamic-loading rockburst. Dynamic-loading rockburst(DR) isa sudden instability phenomena under coupled dynamic and static loading. However theexsiting rockburst mechanism is mainly from nature of coal and compound coal-rockangles, and the study on the effect of coupled static and dynamic loading on nature of coaland compound coal-rock is few.Based on the occurrence characteristics of DR, first proposed and designed to improvethe Hopkinson bar experiment, and combined with the fractal fracture mechanics, wavemechanics, catastrophe theory and chaos theory, analyzed failure characteristics of coal andcompound coal-rock and stress wave propagation mechanism under coupled static anddynamic loading, and discussed the mechanism of DR caused by the significant change ofthe characteristics of coal and coal-rock structure under coupled static and dynamic loading.The seprating source control system for DR was established and was got effective result inproduction practice of Gushan Mine. The main aspects are as the following:(1) Proceeded the improved Hopkinson bar experiment of coal, and based on fractalfracture mechanics, discussed the failure characteristics and outburst proneness of coalunder coupled static and dynamic loading. It is considered that the outburst proneness ofcoal under coupled static and dynamic loadings is stronger than that under static loading,and fractures number of coal and the size of static loading have a significant impact on theeffect of dynamic loading.(2) Based on the occurrence characteristics of DR, combined with dimensionalanalysis method, obtained the9main factors of DR. Proceeded the improved Hopkinsonbar experiment of compound coal-rock, analyzed failure characteristics of compoundcoal-rock, inquired effect of coal-rock structural characteristics on destruction undercoupled dynamic and static loadings. (3) The judgement formula of failure, catatrophic displacement and the total releasedenergy of compound coal-rock under coupled static-dynamic loading are obtained throughtheoretical analysis and time dependent damage model. Discussed the effect of thecoal-rock structural characteristics on the occurrence conditions, roof subsidence andimpact strength of DR. Through establishing nonlinear dynamic model of compoundcoal-rock combination, analyzed the chaotic mechanism in the occurrance process of DR.(4) By the improved Hopkinson bar experiment of compound coal-rock and wavemechanics, inquired stress wave propagation mechanism and energy dissipationsignificantly under coupled dynamic and static loading, discussed the effect of coal androck mass destruction on propagation and dissipation of dynamic loading. It is consideredthat When the dynamic and static loading are both large, more dynamic loading willinvolved in the destruction of compound coal-rock, otherwise dynamic load will be mainlyreflected or transmitted.(5) Based on summing up the theoretical and experimental results, proposeddisturbance instability mechanism for DR. And based on disturbance instability mechanism,initially established the seprating source control system for DR. The dynamic preventionpractice of Gushan Coal Mine shows that the seprating source control system for DR caneffectively promote safe production ultimately. |
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