地铁隧道液氮与盐水复合冻结原位修复技术研究与分析  

Research and analysis on the in-situ repair technology of subway tunnels using a combination of liquid nitrogen and saltwater freezing

作　　者：周树清 刘林林 王宗金 亓燕秋 林键 邓文杰 ZHOU Shuqing;LIU Linlin;WANG Zongjin;QI Yanqiu;LIN Jian;DENG Wenjie(China Coal Third Construction Engineering Group Com pany Limited,Suzhou 234000,China;China Coal Special Drilling Company Limited,Hefei230001,China;College of Civil Engineering,Anhui Jianzhu University,Hefei 230601,China)

机构地区：[1]中煤第三建设(集团)有限责任公司,安徽宿州234000 [2]中煤特殊凿井有限责任公司,安徽合肥230001 [3]安徽建筑大学土木工程学院,安徽合肥230601

出　　处：《建井技术》2024年第6期29-35,共7页Mine Construction Technology

基　　金：国家自然科学基金(52304073)。

摘　　要：在对国内城市基础设施地下工程领域中突遇水涌砂现象的应急处理技术进行深入分析的基础上,针对国内外在处理软弱含水丰富的地层时所使用的封水和加固技术中存在的问题,提出了一种结合液氮和盐水的复合冻结施工方法,以应对紧急情况。针对在复杂建筑环境中进行的浅埋大断面隧道暗挖作业中地下水流动可能对土体造成的侵蚀问题,提出了一种隧道加固填充技术。考虑到在低温条件下,常规水泥浆和含水材料容易结冰并导致堵塞的问题,提出了一种使用盐水水泥浆进行填充和冻结管施工的技术。通过现场监测所收集的数据,对所提出技术的有效性进行了评估。研究结果表明:①在冻结过程中,地层温度和地表沉降变形得到了有效控制,成功形成了加固体和止水屏障,这不仅缩短了液氮和盐水的冻结周期,还提高了冻结壁的质量;②液氮冻结技术在暗挖开洞区域起到了封闭和加固的作用,确保了在排水和清淤过程中基坑和隧道的密封性,同时有效抵抗了水土压力,并且切断了完好隧道与周围土体的联系,增强了隧道的稳定性;③通过结合液氮的快速冻结特性和盐水的加固效果,该技术不仅显著缩短了修复时间,还显著提升了施工过程的安全性。该技术的成功应用,为地铁隧道在复杂地质条件下的修复提供了有效的技术支持,具有重要的工程价值和社会效益。Based on an in-depth analysis of emergency handling techniques for the phenomenon of water gushing and sand eruption in the field of urban infrastructure underground engineering in China,and in response to the problems existing in the water sealing and reinforcement technologies used in soft and water-rich strata at home and abroad,a composite freezing construction method combining liquid nitrogen and brine has been proposed to cope with emergencies.Firstly,in the case of shallow-buried large-section tunnel excavation in complex building environments where groundwater flow may cause erosion to the soil,a tunnel reinforcement filling technology has been proposed.Subsequently,considering the problem that conventional cement slurry and water-containing materials are prone to freezing and blocking under low-temperature conditions,a technology using brine cement slurry for filling and freezing pipe construction has been proposed.Finally,the effectiveness of the proposed technology was evaluated through data collected by on-site monitoring.The research results show:①During the freezing process,the temperature of the stratum and the surface settlement deformation were effectively controlled,successfully forming a solidified body and a water stop barrier,which not only shortened the freezing cycle of liquid nitrogen and brine but also improved the quality of the freezing wall;②The liquid nitrogen freezing technology played a role in sealing and reinforcing the excavated area,ensuring the sealing of the foundation pit and tunnel during drainage and dredging,effectively resisting water and soil pressure,and cutting off the connection between the intact tunnel and the surrounding soil,enhancing the stability of the tunnel;③By combining the rapid freezing characteristics of liquid nitrogen and the reinforcement effect of brine,the technology not only significantly shortened the repair time but also greatly improved the safety of the construction process.The successful application of this technology provides effective t

关 键 词：地铁隧道 液氮冻结 冻土帷幕 隧道开挖 原位修复技术 

分 类 号：U455.49[建筑科学—桥梁与隧道工程]