Polymer optical fiber sensors for the civil infrastructure

摘要

This paper presents intrinsic polymer fiber (POF) sensors for high-strain applications such as the performance-based assessment and health monitoring of civil infrastructure systems subjected to earthquake loading or morphing aircraft. POFs provide a potential maximum strain range of 6-12%, are more flexible that silica optical fibers, and are more durable in harsh chemical or environmental conditions. Recent advances in the fabrication of singlemode POFs have made it possible to extend POFs to interferometric sensor capabilities. Furthermore, the interferometric nature of intrinsic sensors permits high accuracy for such measurements. A formulation for the sensor response is presented, including the finite deformation of the POF cross-section at high strain values and nonlinear strain optic effects in the polymer. In addition, the design of a time-of-flight interferometer for phase measurements over the large strain range required is outlined. Afterwards, initial measurements of the mechanical response of the sensor at various strain rates are presented. Finally the bond strength of specimens with the POF embedded in various structural materials is investigated.