To study the deformation and settlement characteristics of tunnel lining structures, a tunnel lining structure model was designed based on distributed fibre optic sensing technology. Compared to the cylindrical model used in traditional tunnel lining structural model experiments, in this study, a reinforced concrete structural model was adopted, which can embed fibre optics in the structure, which is closer to actual tunnel engineering conditions. Central and symmetrical concentrated loading experiments were carried out with a simply supported reaction frame. The results of the distributed fibre optic monitoring were compared and analysed with those of traditional monitoring methods to verify the reliability of the distributed fibre optic monitoring results. The numerical simulations of the experiments were conducted by using finite element analysis. By comparing and analysing the simulation and experimental results, the correctness of the simulation calculation results were verified. On this basis, the impact of concrete strength, circumferential reinforcement spacing, and longitudinal reinforcement strength on the deformation and settlement of the tunnel lining structure were analysed. The results show that the hierarchical effect of the strain monitoring results obtained by the embedded fibre optic is more obvious, indicating that the radial monitoring effect of the embedded fibre optic on the tunnel structure is less affected by other external factors than the strain gauge, and the monitoring data are more accurate and effective, with good engineering characteristics. Improving the concrete strength, appropriate circumferential reinforcement spacing, and increasing the longitudinal reinforcement strength can effectively enhance the ability of the structure to resist deformation at the stress location. These factors play a significant role in improving the overall resistance to deformation and safety of the structure. The research results provide a theoretical basis and experimental data for the application of distributed fibre optics in monitoring the deformation and settlement of tunnel lining structures.

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基于分布式光纤传感技术的隧道衬砌结构变形沉降特性研究

为了研究隧道衬砌结构的变形和沉降特性，设计了基于分布式光纤传感技术的隧道衬砌结构模型。与传统隧道衬砌结构模型实验中使用的圆柱模型相比，本研究采用了钢筋混凝土结构模型，该模型可以在结构中嵌入光纤，更接近实际的隧道工程条件。使用简支反应框架进行中心和对称集中加载实验。将分布式光纤监测结果与传统监测方法进行对比分析，验证分布式光纤监测结果的可靠性。实验的数值模拟是通过有限元分析进行的。通过仿真与实验结果的对比分析，验证了仿真计算结果的正确性。在此基础上，分析了混凝土强度、环向钢筋间距、纵向钢筋强度对隧道衬砌结构变形沉降的影响。结果表明，嵌入式光纤获得的应变监测结果的层次效应更加明显，说明嵌入式光纤对隧道结构的径向监测效果比应变片受其他外界因素的影响更小，并且监测数据更加准确有效，具有良好的工程特性。提高混凝土强度、适当的周向钢筋间距、增加纵向钢筋强度，可以有效增强结构在受力位置抵抗变形的能力。这些因素对于提高结构的整体抗变形能力和安全性具有重要作用。研究成果为分布式光纤在隧道衬砌结构变形沉降监测中的应用提供了理论基础和实验数据。