朱仙庄煤矿特厚煤层变间距覆岩坚硬顶板控制技术

Control Technology for Hard Roof of Variable Spacing Overburden Rock in Extra-Thick Coal Seam of Zhuxianzhuang Coal Mine

煤层的巨厚坚硬顶板滞后垮落对采煤工作面矿压显现具有重大影响,通常采取超前预裂措施降低顶板悬跨长度。以淮北矿业集团朱仙庄煤矿883-1工作面覆岩巨厚砾岩顶板治理为背景,针对工作面煤层与巨厚砾岩之间的距离变化特点,划分了巨厚顶板重点控制区域。在特厚煤层覆岩层位结构分析的基础上,得到了覆岩给定载荷,分析了层间距变化对采场矿压的影响,确定了覆岩控制目标层,设计了炮孔空间布置参数。采用高性能煤矿水胶炸药配合多向聚能管和注浆封孔工艺,对煤层的坚硬顶板实施了深孔爆破,取得了良好的坚硬顶板爆破致裂效果,采场巷道围岩变形及工作面矿压显现得到了有效控制。

The lagging collapse of the extra-thick and hard roof of the coal seam poses a significant threat to the mining face.Usually,advanced pre-splitting measures are taken to reduce the span length of the roof.Taking the management of the extra-thick conglomerate roof at the 883-1 working face of the Zhuxianzhuang Coal Mine as the research background,key control areas of the extra-thick roof were identified based on the distance variations between the coal seam and the extra-thick conglomerate.On the basis of the structural analysis of overburden strata in extra-thick coal seam,the given load of the roof was obtained,the influence of the variation of the interlayer distance on the mining pressure was analyzed,the control target layer of overburden strata was determined,and the spatial layout parameters of boreholes were designed.By using high-performance coal mine water-gel explosives combined with multidirectional cumulative tubes and grouting sealing technology,deep hole blasting technology practice was carried out on the hard roof of coal seams,achieving good cracking effect of hard roof blasting.The deformation of the surrounding rock of the mining roadway and the manifestation of mining pressure on the working facewereeffectively controlled.