Non-destructive Measurement of Fiber Embedding Depth in Degradation Detection Sensor of FRP Hydrochloric Acid Storage Tank

Abstract

A non-destructive method for measuring the fiber embedment depth of an optical fiber sensor used to detect degradation of an FRP hydrochloric acid storage tank was investigated. Ultrasonic and optical coherence tomography （OCT） measurements were performed on sensors with various fiber depths, and their accuracies were compared. As a result, it was determined that the OCT measurement was more accurate and relatively effective. The validity of the hydrochloric acid penetration rate calculated from the fiber depth measured by OCT and the discoloration start time of the sensor module when immersed on one side was also examined.