大纵坡长斜井富水软岩地层地面高压预注浆施工方案  

Construction Scheme of Ground High-pressure Pre-grouting in Water Rich Soft Rock Stratum of Long Inclined Shaft with Large Longitudinal Slope

作　　者：吴跃帮 杨再涛 马红钧 王康 李世民 张楚 邓兴飞 WU Yuebang;YANG Zaitao;MA Hongjun;WANG Kang;LI Shimin;ZHANG Chu;DENG Xingfei(POWERCHINA SINOHYDRO ENGINEERING BUREAU 14 CO.,LTD.,Kunming 650041,China)

机构地区：[1]中国水利水电第十四工程局有限公司,云南昆明650041

出　　处：《云南水力发电》2024年第9期117-121,共5页Yunnan Water Power

摘　　要：滇中引水工程太安2号施工支洞(斜井)处断层破碎带内且剩余洞段赋存距离长,面临“无水变形、溜渣,有水变形、突泥”复合型地质灾害侵扰的困境,碎粉岩可灌性差,采用“洞内超前加固”治理耗时长、灌浆费用高昂,直面不良地质安全风险大;为打破困局,引进石油行业定向钻技术、煤炭行业高压预注浆技术,结合该技术在该工程涌水突泥深孔高压预注浆实施成效(太安1号洞),以及深大新增竖井极富水复杂井筒防治水经验(新增27竖井),采用分类治理,复杂问题简单化,将隧洞“超前加固+超前堵水”综合治理需求简化为“超前堵水”,降低治理难度。在地表布设钻场施工“L”型钻孔,对目标洞段周边地层进行超前注浆堵水加固,形成帷幕固结圈,根据开挖揭露情况辅以洞内超前灌浆,在帷幕圈内进一步针对性的灌浆补强,加固围岩从而提高隧洞开挖支护效率,使得工期和投资能够满足工程要求。Tai'an No.2 construction support tunnel(inclined shaft)of the Dianzhong Water Diversion Project is located in a fractured fault zone and the remaining tunnel section has a long distance of occurrence,facing the dilemma of"no water deformation,slag slip,water deformation,and sudden mud"composite geological disasters.The pumpability of the broken powder rock is poor,and the use of"advanced reinforcement inside the tunnel"for treatment is time-consuming and expensive,posing a great risk of adverse geological safety.To break the deadlock,directional drilling technology from the petroleum industry and high-pressure pre grouting technology from the coal industry were introduced.Combined with the implementation effect of this technology in the deep hole high-pressure pre grouting of water inrush and mud burst in the project,as well as the experience of preventing and controlling water in the complex wellbore of the newly added vertical shaft at Shenzhen University,classified treatment was adopted to simplify complex problems.The comprehensive treatment requirement of"advanced reinforcement+advanced water blocking"in the tunnel was simplified to"advanced water blocking",reducing the difficulty of treatment.It sets up drilling sites on the surface to construct L-shaped boreholes,and conducts advanced grouting and water blocking reinforcement on the surrounding strata of the target tunnel section,forming a curtain consolidation circle.Based on the excavation exposure,advanced grouting is supplemented inside the tunnel,and further targeted grouting reinforcement is carried out inside the curtain circle to strengthen the surrounding rock and improve the efficiency of tunnel excavation support,so that the construction period and investment can meet the engineering requirements.

关 键 词：不良地质 超前堵水 超前加固 地面预注浆 “L”型钻孔 帷幕圈 

分 类 号：TV543.5[水利工程—水利水电工程]