Embedded fiber-optic sensors in reinforced concrete elements of bridge structures

Reinforced concrete elements in bridge structures are subjected during their service life to different loading conditions that may affect their durability and efficiency. This can reduce the safety level of the infrastructures over time until their complete degradation. In particular, reinforced concrete elements can develop cracking conditions due to tensile stresses. However, such cracking conditions can propagate leading to the exposure of the steel reinforcement bars to the aggression of external agents such as chlorides. Being able to detect, localize and monitor the development and evolution of cracking can be crucial and this research is aimed at this purpose. In particular, laboratory tests have been performed on reinforced concrete beams that are equipped with embedded and externally applied distributed fiber optics sensors to monitor the state of cracking and its propagation within the thickness.