杭来湾煤矿覆岩导水通道采后注浆封堵技术研究

Investigating the Post-Extraction Grouting Sealant Technology for Water-Conducting Channels in the Overburden of the Hanglaiwan Coal Mine

针对西北水资源紧缺及杭来湾煤矿301盘区采后严重涌水问题,本研究利用地面钻孔注浆技术重建隔水层以堵水。分析显示,该盘区每小时涌水量达975 m^(3),水源来自多层含水层,主要导水通道为采动裂隙等。研究锁定110~140 m深度的导水裂隙,将风化壳裂隙水含水层作为保护关键。通过优化,采用水灰比为0.8、含4%膨润土和8%氢氧化钠的浆液;设计的注浆参数为:压力5 MPa、流量60 L/min,预计扩散半径为66.4 cm;钻孔规格为直径311 mm,套管至基岩,钻孔间距横向为110.5 cm,竖向为97.5 cm。结论认为,该注浆策略技术可为煤矿水资源保护提供科学的实施方案。

Considering the scarcity of water resources in northwest China and the significant water inrush in the 301 block of the Han-glaiwan Coal Mine,this study employs ground drilling and grouting technology to reconstruct the aquifer barrier,thereby mitigating water ingress.Analysis indicates a voluminous hourly water inflow of 975 cubic meters in the affected disk area,sourced from multiple aquifers,with the primary conduit being the mining-induced fractures.This study targets the sealing of water-conducting fissures within the 110~140 meter depth interval,rec-ognizing the weathered crust fracture aquifer as pivotal for containment.Optimization led to the development of a grouting slurry with a water-ce-ment ratio of 0.8,integrated with 4%bentonite and 8%sodium hydroxide;The grouting parameters are meticulously designed as follows:a pressure of 5 MPa,a flow rate of 60 L/min,and an estimated diffusion radius of 66.4 centimetre;Boreholes,311 mm in diameter with casing extended to the bedrock,are strategically spaced at 110.5 centimetre apart horizontally and 97.5 centimetre vertically.The study concludes that the grouting strategy technology can provide a scientific implementation plan for coal mine water resources protection.