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With the increase of subway service time, shield tunnels will produce different degrees of damage and destruction. This is related to external factors such as differences in stratum soil, groundwater seepage, construction disturbance to soil, and operating vehicle load. With the increase of subway service time, shield tunnels will produce different degrees of damage and destruction. This is related to external factors such as differences in stratum soil, groundwater seepage, construction disturbance to soil, and operating vehicle load. In order to ensure the operation safety of the subway, long-term and large-scale safety condition monitoring of the shield tunnel is very important. This study summarizes the technical characteristics, layout methods, data collection and processing of distributed optical fiber in shield tunnel deformation monitoring. The feasibility of distributed optical fiber monitoring technology is verified through the segmental deformation monitoring project of Beijing Metro Airport Line and Line 10 shield tunnel. In addition, some experiences in fiber layout and data processing are summarized, which has reference value for similar projects.

Shield tunnels have different degrees of damage due to the differences in the surrounding soil properties, the disturbance of the soil during construction and the repeated loading of vehicles during operation, and there is a tendency to deteriorate with the increase of subway service time. The long-term and large-scale security status monitoring of shield tunnels is an important guarantee for the safety of subway operation. Two diagnostic algorithms based on strain monitoring data are proposed t in this paper, one is for the openness and dislocation of the segments, and the other is for the uneven settlement of the tunnel. The effectiveness of the two algorithms is verified by distributed optical fiber monitoring data of Beijing Metro Line 10. The calculation results are also compared with traditional monitoring methods. The proposition of these two algorithms provides a new idea for the analysis of distributed optical fiber shield tunnel monitoring data, which is beneficial to the promotion of distributed optical fiber monitoring technology.