QUASI-CONTINUOUS STRAIN MEASUREMENT METHOD OF REINFORCED CONCRETE MEMBER USING DISTRIBUTED FIBER-OPTIC STRAIN SENSORS

Abstract

A new implementation technique of Rayleigh Optical Frequency Domain Reflectometry and its measurement accuracy are discussed. A reinforcing bar and reinforced concrete specimen were instrumented with distributed fiber-optic sensor to measure strain profiles distributed along the specimens. The reinforcing bar and reinforced concrete specimens were tested in uniaxial tension. The measured strain profiles were compared to traditional electrical resistance strain gauges (RSG) to verify the reliability. Compared with the results coming from RSG, it was observed the fiber-optic sensor provided reliable measurements. The distributed fiber-optic sensor was able to detect the formation of cracking and pinpoint the bond deterioration zone.