顶底双软型薄煤层快速沿空留巷技术研究

Study on technology of gob-side entry retaining in thin seam surrounded by soft roof and floor

针对顶底板双软型薄煤层工作面特殊开采条件,分析了沿空留巷的技术难点与关键技术。采用理论分析与数值模拟方法研究了薄煤层沿空留巷围岩破坏特征及变形规律,建立了薄煤层综采面沿空留巷结构模型,通过方案数值模拟对比分析,揭示了薄煤层综采面快速沿空留巷基本原理,提出"采空区预先垒砌矸石袋,巷道内及时构建胶结充填体和铰接顶梁与单体支柱巷内滞后补强支护"的沿空留巷方案,实现了顶底板双软型薄煤层综采面快速沿空留巷。赵官能源煤矿的工程实测表明:巷道顶板下沉量最大仅为197 mm,底鼓量为83 mm,巷道两帮移近量为327 mm,工作面留巷效率达到18 m/d。

In response to the special mining condition of the weak roof and floor in the working face of the thin seam, the difficulties and key technology of gob-side entry retaining in thin seam have been proposed. By using the theory analysis and numerical simulation, the failure characteristics and deformation law of surrounding rocks of gob-side entry retaining in thin seam have been analyzed. The structure model of gob-side entry retaining has been set up in thin seam coal mining. At the same time, Through the numerical simulation analysis and expounding the basic principle gob-side entry retaining in thin seam, it has been put forward that the optimization scheme of gob-side entry retaining was to ＂built waste stone wall in the goaf first, then timely build cemented filling body and long steel beams and monomer pillar support in roadway at last＂. Accordingly, the gob-side entry retaining speed was improved obviously. The result of the actual measurement in Zhaoguan coal mine shows that the roof subsidence is only 197 mm; the floor heave is 83 mm;the convergence of two ribs is 327 mm, consequently, the mining efficiency reached up to 18 m/d.