Study on the embedded fiber-optic strain sensors of white light interference type

More and more fiber optic sensors are used in concrete structural health monitoring in the past several years. In this paper, we aim at the design and fabrication of the white light interferometric fiber optic strain sensor used in concrete structures. This design is focused on the low-cost and high performance. The principle of the white light interference and the fabrication craft of the sensor are discussed. The fiber optic strain sensors and the traditional strain gauge are embedded in a 5-meter-long concrete model beam together to make a contrast test. The experiments were carried out using the PEM-500 A hydraulic test machine. The result shows that the fiber optic strain sensor has good linearity and reliability. The accuracy of the fiber optic sensors is better than 0.8 mu epsilon.