Deformation sensor composed of fiber Bragg grating and the strain gauge for use in civil engineering

Monitoring of building structures is an integral part not only during the phase of construction but also during their use throughout their lifetime. Fiber optic technology offers a number of unrivaled features and forms an interesting alternative to these applications. From the point of view of the safety of large building structures such as buildings, bridges or tunnels, increased attention should be paid to the reliability of monitoring devices. One option is to duplicate standard strain-gauge sensors with modern fiber optic sensors such as Bragg grating. This article brings a new hybrid sensory element, which consists of a Bragg grating and a standard foil strain gauge. The proposed sensor was tested in concrete structures and loaded with force and temperature effects. The results show the functionality of the proposed hybrid sensor implemented in concrete structures and the long-term reliability and independence of both parts of the hybrid sensors.