The invention discloses a
fiber grating dislocation gauge with a wedge-shaped structure. The
fiber grating dislocation gauge comprises a sliding head, rectangular-section overhanging beams, a
fiber grating, a driving rod, a limiting plate, a spring, a wedge block, a protective shell and a sliding conduction arm; a sensing part is formed by the sliding head, the overhanging beams, the fiber grating, the driving rod, the spring, the wedge block, and the like; a conduction part is formed by a fixed rod and a sliding rod; the mechanism of the
dislocation gauge is as follows: free ends of the overhanging beams are enabled to slide along an inclined plane of the wedge block by means of the sliding of the sliding head, so that the differential settlement is converted into the deflection at the free ends of the overhanging beams, and the Bragg reflection
wavelength of the sensing fiber grating, which is stuck at the position close to fixed ends of the overhanging beams, is further changed; furthermore, the problem of
cross sensitivity of the fiber grating is solved by using a reference grating method. The fiber grating dislocation gauge provided by the invention is high in measurement accuracy, adjustable, high in environmental adaptability and good in stability, and has a temperature self-compensating function and anti-
electromagnetic interference performance, thus having better
engineering application prospect.