构造发育区薄层灰岩地面定向孔钻探注浆技术

恒源煤矿Ⅱ63采区受温庄向斜构造影响，其地质构造复杂，向斜轴部破碎带及构造裂隙是6煤层底板的主要导水通道，石炭系上统太原组灰岩含水层组是6煤层巷道掘进及工作面回采的主要威胁含水层。为了实现Ⅱ634、Ⅱ635工作面的安全回采，对该治理区域的地层分布、地质构造发育情况及水文地质条件进行了详细分析，设计了地面定向水平孔煤层底板超前探查注浆防治水方案，包括钻孔布置、钻孔轨迹、钻孔结构、浆液类型及注浆参数等。研究了多砂岩含水层造斜段成孔技术、长距离水平孔钻进技术、薄层灰岩钻遇率保障技术及长距离水平孔高压注浆技术，完成了多砂层含水层造斜段成孔及套管下放工作，造斜段长达870 m；完成了长距离水平孔钻进、注浆工作，水平孔段长达959.54 m；完成了薄层灰岩钻遇率保障工作，L₃灰岩含水层钻遇率大于90%，甚至高达100%。不仅实现了治理区域巷道掘进及工作面的安全回采，还提高了施工效率及经济效益。

The ground directional drilling and grouting technology applied to thin limestone in structural development area

The Ⅱ63 mining area of Hengyuan Coal Mine is affected by the Wenzhuang syncline structure, the geological structure conditions are complex. The syncline fracture zone and tectonic fissures are the main water-conducting channels of No.6 coal seam floor. The Carboniferous Upper Yuan Taiyuan Formation limestone aquifer group is the main source of threat to the No.6 coal seam roadway tunneling and working face mining. In order to achieve the safe mining of the Ⅱ634 and Ⅱ635 working faces, the stratum distribution, geological structure development and hydrogeological conditions of the treatment area were analyzed in detail. The grouting prevention and control scheme of ground directional horizontal drilling of coal seam floor in advance exploration is designed, including drilling arrangement, drilling trajectory, drilling structure, grout type and grouting parameters, etc. The drilling technology of inclined section in multi-sandstone aquifer, the technology of long-distance horizontal hole drilling, the technology of ensuring the penetration rate of thin-layer limestone and the technology of high pressure grouting in long distance horizontal hole are studied, the hole forming and casing running in the inclined section of multi-sandstone aquifer have been completed, with the length of the inclined section reaching 870 m; the drilling and grouting work of long distance horizontal hole has been completed, with the length of horizontal hole reaches 959.54 m; the drilling ratio guarantee of thin limestone has been completed, and the drilling ratio of L₃ limestone aquifer is more than 90%, even as high as 100%. It not only realizes the safe mining of roadway excavation and working face in the treatment area, but also improves the construction efficiency and economic benefits.