A Local Displacement Measurement Method Based on Fiber Bragg Grating Sensor

Abstract

A method for measuring local displacement based on a Bragg fiber grating sensor, comprising the steps of selecting the elastic body structure and size, installing and fixing the FBG sensor, and calculating the local displacement of the measured object. Its main principle is that when the measured object is compressed, its deformation will cause the deformation of the elastic body, and then cause the deformation of the fiber grating. According to the formula in the present invention, there is a unique relationship between the deformation of the grating and the local displacement of the measured object. Corresponding to the formula, so the deformation of the measured object can be obtained, and the precise measurement of the local displacement of the measured object can be realized.

Description

technical field [0001] The invention relates to a method for measuring local displacement of a solid surface by using a fiber grating sensor, in particular to a method for measuring local displacement of a solid surface by using the principle of an FBG sensor. Background technique [0002] Traditional solid surface local displacement measurement uses electromagnetic displacement meters, which can measure the displacement between the upper and lower surfaces of the measured object, but it is difficult to accurately measure the local strain and deformation in the middle of the measured object on both sides. However, the local small displacement will affect the calculation of the mechanical properties of the measured object. For example, the mechanical properties of the local small strain of the solid are related to the calculation of the deformation of the adjacent buildings caused by the excavation of the foundation pit, and it will also affect the settlement caused by the tun...

AI Technical Summary

Problems solved by technology

[0002] The traditional measurement of local displacement on a solid surface uses an electromagnetic displacement meter, which can measure the displacement between the upper and lower surfaces of the measured object, but it is difficult to accurately measure the local strain and deformation in the middle of the measured object on both sides.

However, the local small displacement will affect the calculation of the mechanical properties of the measured object. For example, the mechanical properties of the local small strain of the solid are related to the calculation of the deformation of the adjacent buildings caused by the excavation of the foundation pit, and it will also affect the settlement caused by the tunnel excavation. Calculation, etc.

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