Analysis characteristics embedded plastic optical fiber sensors for crack detection in concrete structures

Abstract

Plastic optical fiber (POF) used as sensors to detect cracks in concrete structures. Sensors made using straight, sinusoidal, loop, and triangle configurations. The POF connected to LED light source and photodetector. The light from LED will propagate along the embedded POF in the concrete then received by the photodetector and measured using by Optical Power Meter in the form of output power displayed on the computer. Sensor testing is done by putting pressure on the concrete using the Ultimate Testing Machine until a crack occurs causing the POF in the concrete to experience strain. The strain of the POF sensor will cause power losses, so the light intensity received by the photodetector will be decreased. The best measurements obtained at triangle configuration sensors 60o have characteristics with a range value of 1.975 μW, the sensitivity of 0.790 μW/cm and a resolution of 0.001 cm. Sensors based on POF for measurement of cracks in concrete structures have the advantages like easy fabrication, low cost, simple measurement system, and high sensitivity.