地铁双护盾TBM隧道穿越富水断裂带管片壁后回填注浆技术研究  

Study on Backfill Grouting Behind the Segment of Double Shield TBM Metro Tunnel Crossing Water-bearing Fault Zone

作　　者：刘泉维 杨星 叶守杰 江玉生[3] 赵继增 谭卓林 杨志勇[3] LIU Quanwei;YANG Xing;YE Shoujie;JIANG Yusheng;ZHAO Jizeng;TAN Zhuolin;YANG Zhiyong(Qingdao Metro Line 6 Co.,Ltd.,Qingdao 266427;Qingdao Metro Group Co.,Ltd.,Qingdao 266045;School of Mechanics and Civil Engineering,China University of Mining and Technology-Beijing,Beijing 100083;China Railway No.2 Engineering Group Co.,Ltd.,Chengdu 610031)

机构地区：[1]青岛市地铁六号线有限公司,青岛266427 [2]青岛地铁集团有限公司,青岛266045 [3]中国矿业大学(北京)力学与土木工程学院,北京100083 [4]中铁二局集团有限公司,成都610031

出　　处：《现代隧道技术》2023年第6期255-261,共7页Modern Tunnelling Technology

基　　金：国家自然科学基金(U1261212).

摘　　要：城市地铁双护盾TBM在富水断裂带地层掘进时易面临涌水、围岩自稳性差等问题,而对管片壁后与围岩的间隙进行同步注浆既能够起到止水,又能够起到加固和及时支护围岩的作用。基于此,设计TBM盾尾封堵板结构,提出豆砾石吹填与同步注浆回填的新型施工工艺。首先通过室内试验确定同步注浆浆液的最优配比,然后依据管片预留孔点位及围岩与管片之间的间隙体积提出“三步吹填豆砾石”和“三次注浆”的回填工艺,最后进行现场应用。结果表明:同步注浆浆液的最佳A液配比为粉煤灰∶水泥∶水=2.5∶1∶2,其结石率可达95%,A液∶B液=1∶1的双液浆初凝时间短、抗水稀释能力强;现场采用该工艺后,豆砾石吹填饱满,回填体结构完整,成型隧道结构稳定,管片沉降控制效果良好,无渗漏水现象。For tunnelling through a stratum in water-bearing fault zone by double shield TBM in urban metro construction,the problems such as water inflow and poor self-stability of surrounding rock are very likely to occur.Grouting in the gap between the segment wall and surrounding rock will prevent water inflow,and also reinforce and support the surrounding rock in a timely manner.On this basis,the TBM shield tail blocking plate structure is de⁃signed,and a new construction process is devised that allows pea gravel backfilling and synchronous grouting.First,the optimum mix ratio of synchronous grouting slurry is determined through laboratory test.Then based on the posi⁃tions of the preformed holes of segment and the volume of gap between surrounding rock and segment,the construction process of"three-step pea gravel backfilling"and"three-step grouting"is devised.At last,the process is put to field application.The results indicate:the optimum solution A mix ratio of synchronous grouting slurry is fly ash∶cement∶water=2.5∶1∶2,the concretion rate is up to 95%,and the double-solution grout with solution A∶solution B=1∶1 has the shortest initial setting time and strongest resistance against water dilution.When this process is applied in practi⁃cal work,pea gravel backfilling creates solid mass,the backfilled structure is intact,the formed tunnel structure is stable,segment settlement is effectively controlled,and there is no water leakage.

关 键 词：富水地层 断裂带 双护盾TBM 管片 豆砾石 同步注浆 

分 类 号：U455[建筑科学—桥梁与隧道工程]