基于分布式光纤应变传感的位移检测方法研究
Research on Displacement Detection Method Based on Distributed Optical Fiber Strain Sensing

针对隧道施工过程中拱顶沉降监测，提出了一种基于分布式光纤应变传感的位移检测方法。测量光纤采用三点折线方式部署，研究表明中点的相对位移变化与平均应变呈现二次曲线关系。通过实验验证了位移与应变的曲线关系，对比实验表明位移检测精度达到0.31 mm。本文提出的方法可用于隧道拱顶沉降的长期、连续和实时检测，得益于分布式传感的优点可近一步实现隧道多个位置的同时检测。
A displacement detection method based on distributed optical fiber strain sensing is proposed for the monitoring of dome settlement during tunnel construction. The measurement fiber is deployed in a three-point broken line method, and the study shows that the relative displacement change of the midpoint and the average strain present a quadratic curve relationship. The curve relationship between displacement and strain is verified through experiments. Comparative experiments show that the displacement detection accuracy reaches 0.31 mm. The method proposed in this paper can be used for long-term, continuous and real-time detection of tunnel vault settlement, benefiting from the advantages of distributed sensing, it can realize the simultaneous detection of multiple locations in the tunnel in one step.