In this paper, an investigation into the suitability of using fibre Bragg gratings (FBGs) for monitoring the accelerated curing process of concrete in a microwave heating environment is presented. In this approach, the temperature data provided by the FBGs are used to regulate automatically the microwave power so that a pre-defined temperature profile is maintained to optimize the curing process, achieving early strength values comparable to those of conventional heat-curing techniques but with significantly reduced energy consumption. The immunity of the FBGs to interference from the microwave radiation used ensures stable readings in the targeted environment, unlike conventional electronic sensor probes.
A novel sensing approach has been developed for in-situ corrosion monitoring of steel in reinforced concrete structures, using a fibre loop interferometer sensor system based on a Hi-Bi photonic crystal fibre (PCF). To do so an accurate fibre alignment procedure has been implemented in order to improve the performance of the sensor system embedded into the concrete structure when it is subjected to an accelerated corrosion test. The positive results obtained have confirmed the effectiveness of such a sensor system for applications in structural health monitoring.