Fibre-optic sensors assess tunnel safety
Fibre optic sensor technologies show great promise in monitoring and assessing civil structures such as tunnels and also account for seismic stability and life cycle. Small and medium-sized enterprises (SMEs) specialising in fibre optic structural sensing will have opportunities to enhance safety and increase competitiveness in the construction sector. The EU-funded project MONICO worked on strengthening SMEs in the field. MONICO developed and produced an advanced fibre optics sensing system for monitoring the structural condition and seismic loading of reinforced concrete in tunnels. The sensors are embedded in concrete for the life-cycle measurement of deformation and they wirelessly transmit crucial data on seismic disturbances. A sensor data processing module to filter out noise and false inputs was also produced for integration into the fibre optic system. The project team also studied two different monitoring systems, namely a Bragg grating fibre optic-based monitoring system and a distributed fibre optics sensing system. It assessed the pros and cons of both to study how they can be exploited for the project purposes, either alone or in combination. Development of the system also included different components such as interrogation unit and reliable wireless communication capability, both under normal conditions and during an earthquake. After intense testing, calibration and validation of the various parts, the system was completed and approved by the civil engineering partners. Assessing the lifetime of civil structures will lead to improved environmental impact and cost effectiveness, making the new system an important tool in construction and engineering. Fibre optic sensors also represent one of the most promising market segments, increasing the competitiveness of the industry in the EU. Efforts have been made to exploit the project's results by identifying customers and positioning the technology in the market, bringing Europe one step closer to safer tunnels and structures.
Keywords
Tunnel, structural integrity, seismic stability, reinforced concrete, sensor technologies, fibre optics, civil engineering
