Simultaneous distributed measurement of the strain and temperature for a four-point bending test using polarization-maintaining fiber Bragg grating interrogated by optical frequency domain reflectometry

摘要

We demonstrate a simultaneous distributed strain and temperature measurement technique with the spatial resolution of 1 mm using fiber Bragg gratings inscribed in a polarization-maintaining and absorption-reducing fiber (PANDA-FBGs) and optical frequency domain reflectometry (OFDR). We conduct four-point bending tests in an environmental chamber. Using high birefringent PANDA-FBGs that are manufactured specifically for the simultaneous measurements, the uniform temperature distributions and the typical strain distribution profiles of the four-point bending tests were successfully obtained. The measurement errors of strain were from 31 ge to 19 and of temperature were from -0.9 degrees C to 1.3 degrees C. The spatial standard deviation was 7.5 mu epsilon and 0.9 degrees C. We also discussed the effect of the residual strain of the sensor-bonding procedures and the data averaging. (C) 2016 Elsevier Ltd. All rights reserved.