煤矿微型TBM及其掘进瓦斯治理巷道工程实践

Coal mine micro TBM and its applications on excavation of coal seam gases drainage roadways

全断面掘进机(TBM)已在煤矿深井岩巷掘进中得到成功应用,其施工安全性好、掘进速度快,可安全高效地施工煤矿瓦斯、水害治理巷道,缓解了煤矿采掘接替失调的问题。为提高TBM在深井煤矿中使用的灵活性,扩大TBM在煤矿深井岩巷掘进中的应用范围,提出了煤矿微型TBM设计原则和技术指标,包括煤矿微型TBM在整机及部件尺寸重量、设备防爆和地层适应性等方面需满足的要求及解决方案。确定了煤矿微型TBM结构型式和主要参数,研发了煤矿微型TBM。系统论证了煤矿微型TBM设备及施工工艺研发中的技术难点与解决方案。针对煤矿微型TBM掘进瓦斯治理巷道工程地质条件,开展不同支护工况下煤矿微型TBM掘进巷道围岩稳定性数值分析。根据数值分析结果,综合考虑支护效果与支护效率,优选巷道支护方案,并开展巷道围岩变形与锚杆轴力现场监测。监测结果表明,巷道掘进后20天内,围岩变形和锚杆轴力增速较快;65天以后,围岩变形趋于停止,锚杆轴力也停止增长。巷道正顶处锚杆轴力略大于肩窝和帮部,巷道围岩整体稳定性较好,所选锚网支护形式可有效控制围岩收敛变形。采用煤矿微型TBM施工煤矿瓦斯治理巷道,锚杆支护施工效率能够理想地匹配煤矿微型TBM的掘进速度,巷道平均月进尺300 m,实现单班最高进尺15 m,圆班最高进尺41.6 m,相比钻爆法掘进效率提高了3~6倍。

TBMs had been successfully applied in the excavation of deep-buried roadways in coal mines due to its good construction safety and fast tunneling speed.TBMs are able to safely and efficiently excavated roadways for gas and water hazard controlling in coal mines,and alleviates the problem of misalignment in coal mine excavation.In order to improve the flexibility of TBMs used in deep-buried coal mines and expand the application range of TBMs in deep coal mine roadway excavation,the design principles and technical indicators of coal mine miniature TBMs are proposed,including the size and weight of the whole machine and components,the explosion-proof,formation adaptability,and solutions that need to be met of coal mine micro TBMs.The configurations and main parameters of the coal mine micro TBM were determined,and the coal mine micro TBM was designed and manufactured.The technical difficulties and solutions in the research as well as development of coal mine micro-TBM and construction technology are systematically demonstrated.According to the engineering geological conditions of gas drainage roadway in coal mine micro-TBM tunneling,numerical analysis of surrounding rock stability of micro TBM exvated coal mine roadway under different support conditions is carried out.Based on the numerical analysis results,comprehensively considering the support effect and support efficiency,the roadway support scheme is optimized,and the in-situ monitoring of the deformation of the roadway surrounding rock and the axial force of the rokbolts are implemented.The monitoring results show that,within 20 days after the roadway excavation,the deformation of the surrounding rock and the axial force of the rockbolt increase rapidly.About 65 days after the excavation,the deformation of the surrounding rock tends to stop,and the axial forces of the rockbolts also stopped increasing.The axial forces of the rockbolts which are installed on the roadway roof are slightly larger than those of installed on the shoulder and sides.The overall stability of the surrounding rock of the roadway is good,which can meet the requirements of subsequent gas control projects.Excavating coal mine gas drainage roadways by using micro TBMs,the efficiency of roadway supporting meets the requirements of penetration rates of micro TBM.The average heading speed reached up to 300 m/mth,the highest heading speed are 15 m/shift and 41.6 m/d.the heading speed of micro TBM 3~6 times of drilling and blasting.