孙如达,夏永学,高家明. 中高位厚硬顶板长孔水力压裂防冲效果研究[J]. 煤矿安全, 2023, 54(7): 69-77.
    引用本文: 孙如达,夏永学,高家明. 中高位厚硬顶板长孔水力压裂防冲效果研究[J]. 煤矿安全, 2023, 54(7): 69-77.
    SUN Ruda. Study on anti-impact effect of hydraulic fracturing for long holes in medium and high thick hard roof[J]. Safety in Coal Mines, 2023, 54(7): 69-77.
    Citation: SUN Ruda. Study on anti-impact effect of hydraulic fracturing for long holes in medium and high thick hard roof[J]. Safety in Coal Mines, 2023, 54(7): 69-77.

    中高位厚硬顶板长孔水力压裂防冲效果研究

    Study on anti-impact effect of hydraulic fracturing for long holes in medium and high thick hard roof

    • 摘要: 针对于门克庆煤矿3106工作面厚硬顶板卸压效果不足的问题,通过现场微震监测的微震高能事件活跃层位和理论分析确定了3106工作面顶板诱冲关键层,提出了长孔水力压裂技术并进行了现场应用,分析评判了压裂效果和卸压效果。结果表明:距离煤层平均高度59.33 m、厚度49.95 m的砂岩层为诱冲的关键层;实施水力压裂后,在关键层内预制了裂隙面,裂隙内含水量增加,视电阻率的连续性增强,出现了降阻现象;水力压裂削弱了关键层的整体性和强度,微震能量转为“高频低能”释放,大能量事件平均延米发生密度和延米释放能量分别降低了55%和79%,回采期间现场未发生大能量矿震等动力现象;工作面来压步距缩短,来压强度降低,动载系数整体显著减小,且呈逐渐下降趋势;工作面回采压裂区域后的地表沉降斜率增加,厚硬顶板垮落更充分。研究证实了长孔水力压裂技术在防冲工程中的有效性和可行性,实现了工作面的安全开采。

       

      Abstract: In view of the insufficient pressure relief effect of thick hard roof of 3106 working face in Menkeqing Coal Mine, the key layer inducing roof shock of 3106 working face was determined by the active strata of micro-seismic high-energy events monitored in the field and theoretical analysis. The long-hole hydraulic fracturing technology was proposed and applied in the field, and the fracturing effect and pressure relief effect were analyzed and evaluated. The results show that the sandstone layer with the average height of 59.33 m and the thickness of 49.95 m from the coal seam is the key layer to induce shock. After hydraulic fracturing, the fracture surface is prefabricated in the key layer, the water content in the fracture increases, the continuity of apparent resistivity is enhanced, and the resistance reduction phenomenon appears. Hydraulic fracturing weakens the integrity and strength of the key layer, and the micro-seismic energy is released into “high frequency and low energy”. The average occurrence density and energy released in long meters of large energy events are reduced by 55% and 79%, respectively. No dynamic phenomena such as large energy mine earthquakes occur in site during mining. The compression step distance of the working face is shortened, the compression strength is reduced, and the dynamic load coefficient decreases significantly and gradually. The slope of surface settlement increases after mining fractured zone in the working face, and the thick hard roof collapses more fully. This study confirmed the effectiveness and feasibility of long-hole hydraulic fracturing technology in anti-impact engineering, and realized the safe mining of working face.

       

    /

    返回文章
    返回