The Leakage Monitoring Test Research Based on Distributed Optical Fiber Temperature Sensing

摘要

The operating principles of seepage positioning and quantitative monitoring based on distributed optical fiber temperature sensing technique were introduced in this paper.The indoor seepage monitoring model and the ideal optical fiber arrangement method to improve the seepage monitoring spatial accuracy were designed.In order to determine the rationality of optical fiber bending radius, a temperature calibration test was carried out between the optical fiber winded on the PVC tubes and the unwinded optical fiber.Then, the seepage simulation test was implemented through heating the optical fiber buried in the clay, fine sand, and 4 kinds of mixed soil in which the quality ratio of clay and fine sand are 4:1, 3:2, 2:3 and 1:4, respectively.It was shown that the rationality of the optical fiber arrangement and the feasibility of seepage quantitative monitoring through comparing and analyzing the optical fiber temperature rise values of different seepage flows.In the end, the effective measures of improving the temperature measuring accuracy and compaction effect in the test were discussed.