基于FBG(光纤光栅)监测技术的地铁盾构隧道环向变形研究  

Research on Circumferential Deformation of Metro Shield Tunnel Based on FBG Monitoring Technology

作　　者：代兴云 穆保岗[2] 陶津[2] DAI Xingyun;MU Baogang;TAO Jin(China United Engineering Corporation Limited,310052,Hangzhou,China;Civil Engineering College of Southeast University,211189,Nanjing,China)

机构地区：[1]中国联合工程有限公司,杭州310052 [2]东南大学土木工程学院,南京211189

出　　处：《城市轨道交通研究》2024年第6期148-152,160,共6页Urban Mass Transit

基　　金：中国联合工程有限公司重点技术开发项目(2023ZD-01)。

摘　　要：[目的]FBG(光纤光栅)监测技术具有动态响应快、抗干扰强、精度高、耐久性强等优点,能实现远距离实时监测,其反馈的环向变形监测数据对盾构掘进过程的参数调整有着重要意义,有必要基于光纤监测技术对管片环向变形规律进行深入研究。[方法]以某地铁隧道工程为例,采用光纤传感器对地铁隧道施工期管片进行实时监测。通过监测数据分析,研究管片施工环境中的环向应变变化规律,分析相对收敛位移与盾构掘进参数之间的相互关系。[结果及结论]监测数据表明,环向变形主要集中在管片安装之后的一周内和相邻隧道掘进的50 m范围内,当地层差且埋深小时,后掘进隧道对已施工管片收敛的影响程度为50%;当地层好且埋深大时,而后掘进隧道对已施工管片收敛的影响程度约为65%~83%。不同埋深时管片应变受土层及邻线隧道施工的影响较大,其中埋深小且土层差的管片变形变化大,埋深较大的管片约束性较好,变形变化不明显。相对收敛位移与盾构掘进参数存在明显的联系,盾构的总推力与管片的相对收敛位移存在负相关的关系,盾构的掘进速度与管片的相对收敛位移存在正相关的关系。采用FBG监测技术得到的实时监测数据,能作为盾构机掘进参数调整的依据。[Objective]FBG(fiber bragg grating)monitoring technology features fast dynamic response,strong anti-interference,high precision and strong durability,and can realize long-distance real-time monitoring.The feedback circumferential deformation monitoring data from FBG is of great significance to the parameter adjustment in the process of shield tunneling.Therefore,it is necessary to conduct an in-depth research on the circumferential deformation law of the segments based on FBG technology.[Method]With a metro tunnel project as the example,the fiber optic sensors are used for realtime monitoring of the segments during metro tunnel construction.Through analysis of the monitoring data,the changing law of the circumferential strain in the segment construction environment is studied,and the correlation between the relative convergence displacement and the shield tunneling parameters is analyzed.[Result&Conclusion]The monitoring data indicates that the circumferential deformation mainly occurs within one week after the installation of the tunnel segments and within a 50 m range of the adjacent tunnel excavation.In condition of unfavorable stratum and small buried depth,the effect of the subsequent tunnel excavation on the convergence of the already constructed segments is about 50%.When the stratum is favorable and the buried depth is large,the effect of subsequent tunnel excavation on the above convergence is approximately 65%to 83%.The strain of the segments is affected significantly by the stratum and the adjacent tunnel construction under different buried depths.The segments in a shallow buried depth and poor soil stratum have large deformation,while those in the larger buried depth exhibit better constraint and unnoticeable deformation.There is a clear correlation between the relative convergence displacement and the shield tunneling parameters.The total thrust of the subsequent shield tunneling is negatively correlated with the relative convergence displacement of the previously constructed segments,while the excav

关 键 词：地铁隧道 光纤监测 环向变形 施工期 

分 类 号：U456.31[建筑科学—桥梁与隧道工程] TN25[交通运输工程—道路与铁道工程]