抽采钻孔封孔参数影响特性数值模拟

Numerical Simulation on Influencing Characteristic of Borehole Sealing Parameters

针对绿塘煤矿瓦斯抽采工程现状,结合煤层赋存状况,对影响抽采钻孔封孔工艺的适用范围和效果的关键参数进行数值模拟。通过数值模拟条件分析,建立了数值模型,经过钻孔周围煤体塑性区域数值模拟和钻孔周围煤体位移数值模拟,确定了煤体强度、钻孔直径、埋深、注浆压力等参数影响规律。结果表明:煤体强度降低、孔径增大、开采深度增大、注浆压力不足均会使钻孔周围的破裂带范围增大,煤体向钻孔中心方向的位移增加。

In view of the current situation of gas extraction engineering and the occurrence of coal seam in Lvtang coal mine, it is necessary to simulate the application scope and key parameters of the drilling hole sealing technology. A numerical model is set up through the analysis of numerical simulation conditions. The influence rules of coal strength, borehole diameter, depth and grouting pressure were determined by numerical simulation of plastic area around borehole and coal displacement around borehole. The results show that with the decrease of coal mass strength, the increase of borehole diameter, the increasing of the mining depth and the insufficient grouting pressure all will increase the fracture zone and the coal displacement around the borehole.