Level test system and method based on OFDR optical fiber sensing

Abstract

The invention discloses a level test system and method based on OFDR optical fiber sensing. The level test system comprises a level test component, a heating sensor optical cable, an inclinometer dataacquisition instrument, a photoelectric conversion module, a DTS demodulator, and an OFDR optical fiber data acquisition instrument, an optical fiber data processing and analysis system and a monitoring result display and early warning system. During the test, an inclinometer equipped with a distributed optical fiber strain sensor, a temperature compensation optical fiber and an acceleration sensitive element is connected in series through an optical cable, the heating sensor optical cable is laid on an inclinometer tube, and the inclinometer is lowered along the inclinometer tube, to obtainthe horizontal displacement, strain and seepage field change information of a monitoring point; and after the test data is processed and analyzed by a data processing system, showing that the horizontal displacement of a soil body changes with the depth and the seepage flow graphically. A method of combining optical fiber sensing and traditional inclination measurement is adopted to monitor the horizontal displacement of the soil body. The monitoring method is comprehensive and high in accuracy, and can fully understand the trend of the horizontal displacement of the soil body, and judge the early warning sliding surface in advance.

Description

technical field [0001] The invention relates to a level testing system in the field of geotechnical engineering, in particular to a level testing system and method based on OFDR optical fiber sensing. Background technique [0002] In geotechnical engineering construction, due to the complexity of engineering practice and the variability of site conditions, it is often necessary to monitor the deep horizontal displacement of rock and soil, so as to obtain real-time horizontal displacement information and prevent large-scale engineering accidents. However, due to the deep monitoring depth of geotechnical engineering such as foundation pits and slopes, it is difficult to measure directly, so the inclinometer came into being. [0003] Traditional inclinometers are divided into movable inclinometers and fixed inclinometers. The movable inclinometer needs to lower the inclinometer sensor along the inclinometer conduit by the load-bearing cable, and measure the data at intervals t...

AI Technical Summary

Problems solved by technology

[0005] Purpose of the invention: The present invention provides a level testing system and method based on OFDR optical fiber sensing to overcome the problem that the traditional inclinometer has single monitoring parameters and large errors in horizontal displacement data when measuring the deep horizontal displacement of the soil, and cannot fully obtain the soil. Deformation characteristics, inaccurate judgment of sliding surface

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