Open AccessDesign and Implementation of FBG Three-dimensional Stress Sensor for Complicated Stress Test in Rock Strata
Author(s) -
Shiming Wei,
Zesheng Zhang,
Liqing Zhang
Publication year - 2021
Publication title -
iop conference series. earth and environmental science
Language(s) - English
Resource type - Journals
eISSN - 1755-1307
pISSN - 1755-1315
DOI - 10.1088/1755-1315/693/1/012088
Subject(s) - fiber bragg grating , stress (linguistics) , interference (communication) , calibration , fiber optic sensor , wavelength , finite element method , structural engineering , geology , geotechnical engineering , materials science , acoustics , fiber , computer science , engineering , composite material , physics , optoelectronics , telecommunications , linguistics , philosophy , channel (broadcasting) , quantum mechanics
A fiber Bragg grating (FBG) sensor was presented and designed which was used to monitor the three-dimensional stress independently in rock strata. The sensing elements with FBGs in x, y, and z directions were combined in one intact material, and the stress/strain would be obtained without interference from other directions because each element could deform independently. By numerical modeling, the stress was applied respectively in different directions on the surface of the sensor, and the result revealed that the stress distributed in the direction applied was far more than other directions, which indicated that every element of the sensor was only sensitive to the stress in one direction. To get the relationship between applied stress and wavelength drifts of the FBG sensor, the calibration experiments were carried out, and the sensitivities in x, y, and z direction were obtained. It is of great significance for obtaining complicated stress state in rock strata and achieving intrinsically safe mining in coalmine.