破碎煤岩巷道注浆加固材料试验与应用

Experiment and application of grouting reinforcement material for broken coal and rock in roadway

基于井下断层带煤岩破碎发育、巷道围岩不稳定和煤与瓦斯突出危险性大等难题,为实现巷道过断层破碎带的安全顺利掘进,拟采用水泥-水玻璃(C-S)为注浆材料用于实施注浆固化充填作业。通过对注浆材料进行力学性能检测、倒杯法及黏度测定法等相关试验,探讨了不同水灰比、C-S体积比的浆液试快抗压强度、浆液凝胶时间及黏度特性,研究了不同配比对注浆材料性能的作用规律,结合贵州五轮山煤矿地质条件确定了最优注浆材料配比,最后检验C-S材料的工程适用性。结果表明:应用于该工程最优注浆材料水灰质量比为1∶1,最优C-S浆液体积比为1∶0.5;通过C-S材料注浆加固后,测得工作面区域内最大残余瓦斯含量为2.58 m^(3)/t,瓦斯压力均值为0.15 MPa,K^(1)值为0.19 mL/(g·min^(1/2)),钻削量平均值为1.67 kg/m,工作面煤层瓦斯各项参数值下降较为显著,且均符合防突细则的有关要求;通过注浆固化技术及采用锚杆、锚索网、工字钢棚对巷道进行联合支护,测得巷道煤岩稳定后顶板移近量为115~133 mm,两帮移近量为116~142 mm。结合注浆的涌水治理效果分析,注浆后的涌水治理效果、联合支护效果较好,工作面现场基本未见渗漏水及大块岩石冒落的现象,说明C-S材料的注浆固化取得了较好的效果,可以为类似破碎地层掘进提供有效的技术途径。

Based on the problems of the development of coal and rock fragmentation in the underground fault zone,the instability of the surrounding rock of the roadway,and the high risk of coal and gas outburst,in order to realize the safe and smooth excavation of the road⁃way through the fault fracture zone,it is proposed to use cement-water glass(C-S)for injection.The grout material was used to imple⁃ment the grouting solidification filling operation.Through testing the mechanical properties of the grouting materials,the inverted cup method and the viscosity measurement method and other related tests,the compressive strength,gel time and viscosity characteristics of the slurries with different water-cement ratios and C-S volume ratios were discussed.The effect of different ratios on the properties of grouting materials was studied,and the optimal grouting material ratio was determined in combination with the geological conditions of the Wulunshan coal mine in Guizhou.Finally,the engineering applicability of C-S materials was tested.The results show that the optimal wa⁃ter-cement ratio is 1:1 and the optimal C-S slurry volume ratio was 1∶0.5.After grouting and reinforcement with C-S material,the maxi⁃mum residual gas content in the working face area is measured to be 2.58 m^(3)/t,the average gas pressure is 0.15 MPa,the K^(1) value is 0.19 mL/(g·min^(1/2)),and the average S value of drilling amount is 1.67 kg/m.The various parameters of coal seam gas in the working face decrease significantly,and all of them meet the relevant requirements of the outburst prevention rules.Through the grouting solidification tech⁃nology and joint support of roadway with bolts,anchor cable nets and I-beam shed,the displacement of roof and floor after coal and rock stability of roadway is measured to be 115-133 mm and the two groups move closer to 116-142 mm.Combined with the analysis of the effect of grouting on water inrush treatment,the effect of grouting on water inrush treatment and combined support is good,and there is ba⁃sically no leakage of water and large rocks falling off at the working face,indicating that the grouting of C-S material Solidification has a⁃chieved good results,which can provide an effective technical approach for similar crushed formation excavation.