Relative Horizontal Displacement Sensor Between Layers of Optical Fiber Bragg Grating for Road

Abstract

The present invention provides a road-use optical fiber grating interlayer relative horizontal displacement sensor. According to the technical scheme of the invention, the test on the relative horizontal displacement between layers inside a pavement structure is realized. A top cover is embedded into the bottom of an upper-layer structure. A center column is connected with a top cover and a uniform strength beam, so that the top cover and the uniform strength beam move together. A bottom plate is embedded into the top of a lower-layer structure, and monitors the mutual displacement condition of the above two layers. A fixed ring is used for fixing the top cover and the bottom plate. Under the fixation of the fixed ring, only a tangential displacement is generated between the top cover and the bottom plate, so that the top cover and the bottom plate are not mutually separated. A silica gel pad is placed between the fixed ring and the bottom plate to limit the rotation of the bottom plate and the top cover, so that the top cover and the bottom plate are rebounded after the displacement. A fixed plate is used for fixing the silica gel pad of and other structures, so that the silica gel pad of and other structures are located inside the bottom plate. The uniform strength beam converts the horizontal sliding generated by the sensor into the vertical displacement. A sliding groove is arranged in the bottom plate and a glass cover plate is covered onto the sliding groove to increase the scratch resistance thereof. An optical fiber grating is stuck onto the uniform strength beam by a special structural adhesive, and the deformation of the uniform strength beam is converted into the wavelength change of the optical fiber grating.

Description

technical field [0001] The invention relates to a relative horizontal displacement sensor between layers of optical fiber gratings for roads, and belongs to the technical field of displacement sensors. Background technique [0002] It is extremely important to grasp the real internal mechanical response of the pavement structure. With the development of optical fiber sensing technology, the fiber grating sensor has the advantages of anti-electromagnetic interference, corrosion resistance, high insulation, wide measurement range, and easy reuse into a network. , It has been widely used in civil engineering, aerospace, petrochemical, electric power, medical, shipbuilding and other fields. When the external force on the fiber Bragg grating changes, the strain distribution of the fiber Bragg grating itself changes accordingly, which causes the change of the center wavelength of the fiber Bragg grating; through the fiber Bragg grating demodulation equipment, the change of the cen...

AI Technical Summary

Problems solved by technology

[0003] In some long longitudinal slopes and bus intersections, especially under the action of high temperature in summer and heavy vehicles, the pavement structure often produces interlayer displacement, which can reach 5 or 6 cm in severe cases, which undoubtedly seriously affects the use of roads. life

However, the existing fiber grating displacement sensors can only achieve displacement measurement in a single direction. As the sensor is embedded in the structure, its measurement direction is also fixed, and it is difficult to move under the surrounding pavement materials, making it impossible to carry out Measurement

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