大采高工作面异常区深孔预注浆技术

Deep Hole Pre-grouting Technology in Abnormal Area of Large Mining Height Working Face

为了减小异常区对大采高工作面回采的影响,采用现场注浆实测的方法,研究了异常区煤体裂隙发育规律,提出了注浆加固方案,并进行现场试验。结果表明:异常区煤体裂隙呈现出先张开后闭合的发育规律,裂隙超前工作面40 m开始张开,超前工作面30 m发育到最大值,在30 m以内裂隙出现闭合;最佳注浆区选择在超前工作面40~30 m范围;通过对异常区注浆加固,降低了工作面片帮频次、减小了煤壁片帮深度,为工作面安全高效通过异常区提供条件。

In order to reduce the impact of abnormal area on high mining height working face, the site observation was applied to analyze the fracture development laws of coal seam in abnormal area, and grouting reinforcement scheme is proposed. The results show that the abnormal area of coal fracture shows the development law of the first opening and then closing; the fracture begins to open at advanced working face of 40 m and develops to the maximum value at 30 m; the best grouting area is the 40 m to 30 m range of advanced working face; through the abnormal area grouting reinforcement, the frequency and depth of rib spalling at working face is reduced, which provides the conditions for the working face passing through abnormal area safely and effectively.