Monitoring of surrounding buildings

Determination of the geotechnical influence zone and identification of the buildings to be monitored. Monitoring of vibration levels generated by the works using sensors. Monitoring of building movements using tilt sensors that measure their verticality. Automated topographic monitoring, measuring the position of reference points relative to a fixed base located outside the zone of influence.

Monitoring of geotechnical parameters and structures

Monitoring soil deformation using inclinometers installed in boreholes at various depths. Measurement of settlement, tracking of ground deformation, and monitoring of pore water pressure. Monitoring of tram track degradation caused by vibrations. Manual topographic and inclinometric surveys.

Monitoring of the construction project to increase the capacity of Line A of the Rennes metro, France

To address the continuous increase in ridership on Line A of the Rennes metro, a major construction project has been launched to boost its capacity by 25%.
SOCOTEC Monitoring is supporting this strategic project by providing geotechnical and environmental monitoring of the site, thereby ensuring the safety of users and the preservation of surrounding buildings.

Key informations

Date: 2025
Client: Demathieu Bard
Location: Rennes, Ille-et-Vilaine

Talk to our experts

Bruno NOLEN

Business Development Manager, SOCOTEC Monitoring

bruno.nolen@socotec.com

Project details

In response to increasing ridership, Rennes Métropole has launched a major project to increase the capacity of Line A by 25%, enabling trains to run every 66 seconds (instead of 80–90 seconds currently). This optimization will raise transport capacity from 7,500 to 9,300 passengers per hour per direction.

This project stands out for several strategic infrastructure developments, essential for improving traffic flow, increasing capacity, and ensuring system safety. These include:

The extension of the underground tail track beneath the J.F. Kennedy slab by approximately 200 meters, providing up to five additional stabling positions (instead of four currently), thereby increasing operational flexibility for train turnarounds.
The construction of a second platform at J.F. Kennedy station. Measuring 26 meters in length, it will separate boarding and alighting passenger flows, improving both efficiency and safety.
The relocation of the switch in the tail track area to reduce train turnaround time and increase service frequency.
The construction of an auxiliary structure dedicated to technical requirements: ventilation, smoke extraction, and emergency access. This addition ensures compliance with safety standards and the long-term sustainability of the network.

At the same time, seven new VAL 208 NG3 trainsets will be acquired, increasing the fleet from 30 to 37 trains, with 33 operating simultaneously.

The project, launched in April 2025, will run until 2028. Project management is carried out by Artelia.

Assignments entrusted to SOCOTEC Monitoring

A project of this scale, carried out in the heart of a dense urban area, presents major challenges for the immediate environment. Vibrations, in particular, can affect the structural integrity of nearby buildings.

SOCOTEC Monitoring experts therefore ensure the continuous recording and monitoring of various structural and geotechnical parameters, enabling alerts to be triggered in the event of dangerous structural movements.

Determination of the geotechnical influence zone and identification of the buildings to be monitored.
Monitoring of vibration levels generated by the works using sensors.
Monitoring of building movements using tilt sensors that measure their verticality.
Automated topographic monitoring, measuring the position of reference points relative to a fixed base located outside the zone of influence.

Monitoring soil deformation using inclinometers installed in boreholes at various depths.
Measurement of settlement, tracking of ground deformation, and monitoring of pore water pressure.
Monitoring of tram track degradation caused by vibrations.
Manual topographic and inclinometric surveys.

Measurement of noise levels generated by the construction site to ensure compliance with regulatory thresholds.

Green Trust

The Green Trust program brings together all the solutions offered by SOCOTEC that align with the objectives defined by the European Taxonomy aimed at mitigating the effects of climate change. SOCOTEC supports its clients in their ecological transition efforts.

The broad range of expertise of our specialists enables them to operate in areas such as reducing pollution at industrial sites, minimizing the impact of projects on biodiversity, preparing sustainability reports, and implementing solutions based on circular economy principles.