High-efficiency fontis detection by optical fiber
The need
SNCF Réseau's mission is to ensure the safety of rail traffic. To do this, it monitors the floors and basements on which railway platforms are based, in order to prevent the risk of foundries (localized and surface collapses) that could cause derailments.
In this context, SCNF Réseau agents from the Industrial Engineering Department expressed the need for a high-efficiency basement survey solution, in order to effectively prevent the risks of smelting.
Sercel, a pioneer company in measuring, monitoring and understanding the subsurface, wanted to collaborate with SNCF Réseau's business teams to meet this need, by committing to a 4-month sprint.
The solution
Prior to the sprint, a method for non-destructive investigation of the subsoil using geophysical sensors was developed as part of an R&D collaboration between SNCF Réseau and Sercel. The objective was then to optimize this solution financially by replacing geophysical sensors with optical fiber.
To do this, Sercel tested 2 types of optical fibers, a straight fiber and a helical fiber, with several installation methods, in order to compare their effectiveness.
The experiment
The experimental phase began on October 24, 2022 with the installation of equipment along a high-speed line, in an area subject to cavity hazard (risk zone). Data acquisition started on November 9, 2022 and ended on February 10, 2023.
Apprenticeships
The helical fiber and the straight fiber buried in the trench give consistent results. As expected, the helical fiber allows a better resolution of the results.
At the conclusion of this experiment and in order to obtain optimal resolution, the acquisition parameters were redefined allowing the characterization of anomalous zones already known.
Sercel is a leader in the design of integrated infrastructure monitoring systems. Our field of activity covers geophysics and geotechnics, ranging from the manufacture of geophysical sensors, development of innovative algorithms and deployment services and permanent surveillance, to the delivery of connected alert systems. We developed this industrial expertise within the Viridien group, founded in 1931 (Compagnie Générale de Géophysique), a world leader in geosciences in the field of natural resource exploration. Our vocation is now to promote modern solutions for the surveillance of railways, bridges, tunnels,...
Sercel has developed a solution for the continuous monitoring of geological conditions under railways for SNCF Réseau. In order to develop our expertise and exchange with French railway players, Sercel is a member of FIF and ROL. Over the past two years, our participation in the ROL has allowed us to collaborate on two use cases in ROL, to better and better understand the needs of businesses and to meet manufacturers on collaboration topics.
