大采高工作面切顶卸压沿空留墙技术可行性研究
Feasibility Study on Roof Cutting and Pressure Relief Technology of Gob-side Wall Retaining in Large Mining Height Working Face
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摘要: 为解决大采高工作面沿空留墙混凝土墙体承载大导致墙体大量变形的问题,针对王庄煤业沿空留墙现场条件,对沿空留墙混凝土承载结构进行了确定,计算了混凝土墙体承受载荷与其最大承载能力,提出了采用切顶卸压技术减弱墙体承受载荷。通过数值模拟分析得出采用切顶措施后,可以有效减小工作面侧向支承应力峰值,减小混凝土墙体承受的载荷,降低回采巷道煤帮侧应力集中现象,达到卸压的效果。以数值模拟结果为基础确定采用爆破切顶技术,切顶高度为15 m,并对爆破方案进行了设计。现场实践结果表明,该爆破切顶方案成功起到了卸压护巷的作用。Abstract: To solve the problem of large deformation of concrete wall caused by large bearing capacity of gob-side wall retaining in large mining height working face, the concrete bearing structure of gob-side brick retaining was determined for the site conditions of Wangzhuang Coal Industry. We calculated the load-bearing capacity of concrete wall and its maximum load-bearing capacity, and proposed roof cutting and pressure relief technology to reduce the load on the wall. Through numerical simulation, it is concluded that the peak stress of lateral support of the working face can be effectively reduced, the load on the concrete wall can be reduced, the stress concentration on the coal side of the mining roadway can be reduced, and the pressure can be relieved. Based on the numerical simulation results, the blasting top cutting technology was determined to be adopted, and the height of the roof cutting was 15 m, and the blasting scheme was designed. The practical results show that the blasting roof cutting scheme has successfully played the role of pressure relief and roadway protection.