煤矿覆岩离层注浆减沉技术研究及应用

Grouting and subsidence reduction technology for separated layers of overlying strata at coal mines

针对门克庆煤矿11-3101工作面铁路下压煤问题,为提高煤炭资源回收率,应用离层注浆减沉技术减小地表下沉,通过室内试验测试了不同配比充填料浆的流变特性,确定了合适的料浆配比,同时构建采动覆岩离层演变力学模型,提出了离层动态发育位置及离层开度预测方法。研究结果表明:11-3101工作面从下往上将会产生四个离层,分别位于工作面顶板上方45.42、228.38、337.19、363.99 m处;离层开度从下到上依次为2.62、1.49、1.39和1.33 m,开度随着层高的增长而递减;注浆压力为6.5 MPa,注采比大于45%时,地表倾斜变形值小于3 mm/m,现场监测结果显示铁路路基最大沉降量仅58.72 mm,注浆减沉效果显著。

In order to mine the No.11-3101 working face under the railway at Menkeqing Coal Mine and improve the recovery rate of coal resources,we applied the separation layer grouting technology to solve the ground depression,tested the rheological properties of different ratios of filling slurry through indoor experiments,determined the appropriate slurry ratio,and constructed a mechanical model of the evolution of separated layers in the overburden under mining.Accordingly,we proposed a prediction method for the dynamic development position and crevice width of separated layers.The research results showed that there were four separated layers from bottom to top of the working face,located at 45.42,228.38,337.19 m,and 363.99 m above the working face roof;the crevice width of separated layers from bottom to top was 2.62 m,1.49 m,1.39 m,and 1.33 m,respectively,and the width decreased with the increase of layer level;when the grouting pressure was 6.5 MPa and the grouting-mining ratio was greater than 45%,the surface inclined deformation value was less than 3 mm/m,and the field monitoring results showed that the maximum subsidence of railroad bed was only 58.72 mm,indicating that the grouting had a significant effect on subsidence reduction.