黄河北煤田定向钻孔注浆效果的全周期评价方法

Full Cycle Evaluation of Grouting Effect of Directional Drilling in Huanghe North Coalfield

含水层注浆是治理煤矿底板水害的主要方法之一。为研究定向钻分支孔注浆的实际效果,以山东省邱集煤矿现场注浆作为工程背景,基于源头保障、过程控制、科学分析的注浆效果评价原则,通过钻孔顺层率、注浆终压、浆液流量、透水率、注浆后岩层渗透系数和涌水量等参数从注浆前、注浆中和注浆后3个时期对注浆效果进行全周期综合评价。结果表明,注浆改造后灰岩的渗透系数0.000613 m/d,具备了极微透水岩体的条件,预计煤层开采时底板正常涌水量27.37 m^(3)/h,最大涌水量41.06 m^(3)/h,定向钻孔注浆对岩溶裂隙和导水通道等进行了有效封堵,满足了工作面的回采要求,表明定向钻孔注浆的全周期评价方法是科学合理的。

Aquifer grouting is one of the main methods for controlling water disasters in coal floor.In order to study the actual effect of directional drilling branch grouting,taking the field grouting of Qiuji coal mine in Shandong province as the engineering background,based on the evaluation principles of source guarantee,process control and scientific analysis of grouting effect,the grouting effect is comprehensively evaluated from the three periods of pre-grouting,mid-grouting and post-grouting through the parameters of borehole bedding rate,grouting final pressure,slurry flow,water permeability,permeability coefficient and water inflow after grouting.The results show that the permeability coefficient of limestone after grouting transformation is 0.000613 m/d,which has the condition of extremely micro permeable rock mass.It is expected that the normal water inflow of the floor is 27.37 m^(3)/h and the maximum water inflow is 41.06 m^(3)/h during coal seam mining.The directional drilling grouting has effectively blocked the karst fissure and water diversion channel,which meets the mining requirements of the working face.It shows that the full cycle evaluation method of directional drilling grouting is scientific and reasonable.