Long-term Deformation Monitoring of CERN Concrete-lined Tunnels using Distributed Fibre-optic Sensing

Abstract

The Centre for European Nuclear Research (CERN) uses large and complex scientific instruments to study the basic constituents of matter by operating a network of underground particle accelerators and appurtenant tunnels. Long-term safety and structural health of this critical infrastructure highlighted the need for a sensing plan that could provide remote monitoring and resistance to high radiation. A pilot Distributed Fibre-Optic Sensing (DFOS) system using Brillouin scattering was used to instrument 8 tunnel sections and obtain a first set of short-term readings. These preliminary readings show minor tunnel ovalisation and will be used as baseline for future long-term readings.