| The top-coal weaking technology is one of the key technologies to achieve safe and highly efficient mining of steep and thick coal seam. There contains abundant steep seam mining resources, horizontal section caving is a scientific method to mining this type of coal seam in Urumqi coal region.And it has become the only technology at present. it is very necessary to improve the recovery rate and ensure security and high efficiency coal mining in terms of a reasonable level section and weakening technology.This thesis is aim of the steep thick seam mining of Urumqi coal region, through rock mechanical properties experiments under the influence of miming, we determine the reasonable instability emission, which provide quantitative basis to dynamic disaster of hazard identification and forecasting as steep seam mining process; the results of physical simulation and calculation indicates that: after pre-blasting and water weakening in the seam, the upper-coal and its surrounding rock are obviously damaged, and the coal seam is adequately broken. Fast face advancing and control the even caving speed and quantity can effective mitigation and prevention roof suddenly broken, it can also induces gas pumping out or overflowing. Using loose circle detector, infrared optical drilling and underground pressure monitoring, we conclude that: the coal on the top of face broken seriously, and in 10m range fractured widely, all of these show that the top coal is dampening obvious. Adoption of the mining field indicates: pre-detonation and water technology significantly weakening of coal, meet top coal caving requirements, it improves caving rate, and reduces the chance of spontaneous combustion of coal dust. At last these technologies increase the coal output safe mining.All those offer reference of perfecting mining method on steep thick.Also; it is of great significance to the class extension of coal mining technology process.
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