Fiber grating vertical strain sensor

Abstract

The invention particularly discloses a fiber grating vertical strain sensor, which comprises a fixed base, a hollow supporting column, optical fibers and a sensitive grating, wherein the fixed base comprises an upper base and a lower base, the hollow supporting column is arranged between the upper base and the lower base, the sensitive grating is arranged on the optical fibers and is bonded on the inner wall of the hollow supporting column, the optical fibers enter from the side surface of the upper base, run through the hollow supporting column and go out from the side surface of the lower base, temperature compensation gratings are arranged on the optical fibers which penetrate through the upper base and the lower base, and the two ends of the optical fibers are connected with fiber grating demodulators. The fiber grating vertical strain sensor has the advantages that the similarity between the material of the sensor and the material of an environment is realized through the hollow supporting column, the change of material strain distribution of the base due to embedment of the sensor is effectively avoided, and the measurement of vertical strain of roadbed materials under the effect of external acting force is realized.

Description

technical field [0001] The invention relates to the field of optical fiber sensing, in particular to an optical fiber grating vertical strain sensor for measuring the vertical strain of asphalt pavement. Background technique [0002] Since the 20th century, my country's road traffic construction has developed at an unprecedented speed. More than 95% of my country's high-grade roads are asphalt pavement, the reason is that it has the following good properties: (1) Sufficient mechanical strength, asphalt pavement can well withstand various effects of vehicle loads on the road surface (2) Certain elastic and plastic deformation ability, able to withstand load without damage; (3) Good adhesion with automobile tires, which can ensure driving safety; (4) High shock absorption brought by plastic properties , can make the car run fast, stable and without noise; (5) no dust, easy to clean and wash; (6) easy maintenance, and the asphalt road surface can be recycled. However, we should...

AI Technical Summary

Problems solved by technology

Practice shows that the above method has some disadvantages: it is difficult to combine the test piece block and the structural layer well, the moisture-proof effect is poor, and the solder joints of the strain gauge are easy to fall off

The sensor itself has a high modulus and a large size. As a foreign body, the original stress field of the medium is changed, and the strain field must also be changed, resulting in the deviation of the test data.

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