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Abstract Based on the review of occurrence mechanism of rock burst and control technique in China，the mechanism of break-tip blast is profoundly discussed in deep hole of coal rock. The theory of break-tip blast for preventing rock burst is studied by numerical simulation method. The comparison is done between the stress fields before and after blasting. The result shows that the break-tip blasting ultimately changes the stress distribution of coal rock and markedly decreases the stress of coal rock in the effective range of blasting. The stress peak value reduces and the position of the peak point is far from coal wall. This technique has been applied to the mining condition of steeply pitching seam and sloping seam. The effectiveness of pressure relief is checked through stress monitoring. The result indicates that the stress state of coal rock is effectively changed by the technique of break-tip blast in deep hole. Three periodical breakdowns are detected after break-tip blast in deep hole of coal rock in Huating mine. The pressure is reduced and the periodical pressure is distinct. The bursting risk decreases favoring the safety of the mine.
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Received: 28 April 2007
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