Deep rock-soil body optical fiber inclinometry system based on optical frequency domain reflection technology

Abstract

The invention discloses a deep rock-soil mass optical fiber inclinometry system based on an optical frequency domain reflection technology, which is used for simultaneously realizing deep soil mass displacement monitoring, and is convenient in temperature compensation and simple in system integration. The system comprises a plurality of optical fiber inclination sensing units, an inclinometer tube, an optical frequency domain reflection demodulation module, a wired or wireless transmission module and an angle-displacement calculation module, the plurality of optical fiber inclination sensing units are respectively and fixedly arranged in the inclinometer tube, the optical fiber comprises a strain optical fiber and a temperature information optical fiber, the strain optical fiber is directly adhered to the surface of the equal-strength beam, and the optical fiber is connected with the optical frequency domain reflection demodulation module through an optical fiber transmission line; and the optical frequency domain reflection demodulation module demodulates strain information and temperature information of the optical fiber inclination sensing unit, and transmits the strain information and the temperature information to the inclination angle-deflection calculation module through the wired or wireless transmission module for displacement calculation of the inclinometer pipe, so as to obtain a deep rock-soil body displacement value.

Description

technical field [0001] The invention belongs to the field of deformation monitoring of deep rock and soil, and in particular relates to an optical fiber inclinometer system for deep rock and soil based on optical frequency domain reflection technology (OFDR). Background technique [0002] Geological disasters of high and steep slopes and landslides occur frequently in China, especially in the western mountainous areas, which pose a huge threat to local residents and related railway and highway transportation facilities. In order to protect the personal and property safety of residents and the normal operation of transportation facilities, support structures such as anti-slide piles, retaining walls, and anchor rods will be set up in areas with landslide risks. However, under the influence of unfavorable factors such as precipitation and geological movement, some stable high and steep slopes also have the risk of instability. The displacement of deep rock and soil mass is an...

AI Technical Summary

Problems solved by technology

The electric tilt sensor is cheap and has high measurement accuracy, but its durability is poor and system integration is relatively complicated

The fiber grating tilt sensor is based on the wavelength division multiplexing function, and multiple sensors can be connected in series on one optical fiber. However, due to the uncertain size and position of the displacement and deformation of the rock and soil mass, it may cause the wavelength overlap problem of the series fiber grating tilt sensor. ; At the same time, since the range of the fiber grating is only 6000 ~ 8000με, there are certain constraints on the range or size of the fiber grating tilt sensor

[0010] At present, there is no report on the development of multi-point optical fiber tilt sensors based on OFDR technology to carry out deep rock and soil measurement.

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