Experimental study on a new FBG-based and Terfenol-D inclinometer for slope displacement monitoring

Slope displacement monitoring is an important means for early warning of landslide hazards, which is of great significance for preventing building damage and economic losses. This study describes a new inclinometer based on fiber Bragg grating (FBG) sensing technology and magnetostrictive effects. A series of FBG sensors were attached to the surface of the Terfenol-D to measure the magnetostrictive strain under different magnetic fields. Authors performed multiple sets of calibration experiments in the laboratory to obtain significant results. Furthermore, this study used the linear relationship between the center wavelength of FBG and the rotating angle of Terfenol-D to obtain the relative deflection angle between the rigid elements. The experiments show that the calibration results are in good agreement with the theoretical results. The developed inclinometer has good linearity, high tilt measurement sensitivity and high resolution. (C) 2019 Elsevier Ltd. All rights reserved.