地面加、卸载下地铁盾构隧道管片变形规律及加固效果研究  

Study on Deformation Law and Reinforcement Effects of Metro Shield Tunnel Segments under Loading and Unloading

作　　者：徐浩 李慎奎 吴圣贤 XU Hao;LI Shenkui;WU Shengxian(China Railway Liu Yuan Group Co.,Ltd.,300308,Tianjin,China)

机构地区：[1]中铁第六勘察设计院集团有限公司,天津300308

出　　处：《城市轨道交通研究》2025年第3期175-180,共6页Urban Mass Transit

摘　　要：[目的]鉴于地铁盾构隧道因地面堆载引发管片结构变形、渗漏水等多种病害,直接影响地铁运营安全的现状,结合武汉地铁某区段隧道地面堆载病害治理的案例,对不同堆载、不同加固措施下地铁盾构隧道管片结构变形规律进行深入研究分析。[方法]依托武汉地铁病害治理项目,建立贴合工程实际的三维数值模型,充分考虑盾构隧道管片错缝拼装、螺栓连接等因素影响,统计整理不同条件下隧道结构在地面加、卸载作用下管片的受力变形特性,并与案例实况进行比对,研究分析不同情况下管片的受力特点和变形规律。[结果及结论]研究发现,当地面加载土柱不大于1.3 m时,隧道结构整体安全;当地面加载土柱不大于4.0 m时,隧道结构顶部采取芳纶布加固更为经济合理;当地面加载土柱大于6.0 m时,隧道内部采用全钢环加固更为有效;加固越早实施,效果越好。在加载后再卸载中发现,当地面加载土柱不大于2.0 m时,对其卸载后管片回弹变形幅度可达50%以上;早发现堆载并及时清理是地铁维保关键一环。经与工程实测对照分析,验证了管片变形规律的真实性和加固措施的可行性、有效性。[Objective]Ground loading over metro shield tunnels often causes structural segment deformations,water leakage,and other issues,directly affecting metro operation safety.Based on a case of ground load-induced damage treatment in a Wuhan Metro tunnel interval,the deformation law of metro shield tunnel segments under varying loading conditions and reinforcement measures are investigated.[Method]Using the Wuhan Metro damage treatment project as a basis,a three-dimensional numerical model is developed to reflect actual engineering conditions.The model accounts for factors such as staggered assembly and bolt connections of shield tunnel segments.The stress and deformation characteristics of tunnel segments from ground loading and unloading octions under different conditions are analyzed and compared with case study observations.The stress features and deformation behaviors of segments in different scenarios are examined and analyzed.[Result&Conclusion]It is found that the tunnel structure remains generally safe when the ground soil column loading does not exceed 1.3 m.When the loading does not exceed 4.0 m,adopting aramid fabric reinforcement at the tunnel crown is the most economical and reasonable solution.For loading exceeding 6.0 m,full-steel ring reinforcement inside the tunnel is more effective.Earlier implementation of reinforcement measures yields better outcomes.During unloading after loading,it is observed that when the ground soil column loading does not exceed 2.0 m,the unloading can result in rebound deformations of more than 50%in the segments.Early detection and timely removal of excessive ground loading are critical to metro maintenance comparison with engineering measurements validate the accuracy of the segment deformation law,the feasibility and effectiveness of the reinforcement measures.

关 键 词：地铁 盾构隧道 管片变形 加固效果 

分 类 号：U457.3[建筑科学—桥梁与隧道工程] U455.43[交通运输工程—道路与铁道工程]