In a municipality in Isère, vertical cracks have appeared on the walls of a church. Their presence raised questions about the stability of the building, with no certainty allowing for the determination of the cause or its progression. In light of this uncertainty, a monitoring mission has been entrusted to the company SID, with the aim of assessing the situation and obtaining tangible elements to decide on any potential interventions.
Mission objective: to measure the activity of cracks over time
Le cœur de la mission reposait sur une problématique simple : observer l’évolution des fissures dans le temps afin de déterminer si elles étaient actives ou non.
L’intérêt de cette approche est double : éviter des travaux inutiles en cas de stabilité avérée, ou au contraire, planifier des actions correctives si l’activité est confirmée.
The company SID has thus deployed lightweight instrumentation tailored to the heritage context of the church, with particular attention paid to the non-intrusiveness of the solution and the clarity of the results.
Rapid, precise, and wireless instrumentation
To meet the site requirements, two types of sensors have been installed:
- DELTA L+: connected crack opening measurement sensor with long-range transmission.
- DELTA L: supplementary manual crack sensor, for redundancy on certain critical axes.
The sensors were fixed using a lightweight drilling system, designed to minimise the impact on historical materials. The commissioning was completed in less than a day. Once installed, the sensors began transmitting their data continuously, without the need for on-site intervention.
The measurements allow for precise tracking of the evolution of movements, while correlating them with temperature data. This cross-analysis is essential for distinguishing thermal effects from actual structural movements.
Results and benefits
The first months of observation have highlighted a moderate behaviour of the cracks, with variations mainly correlated to seasonal effects. Thanks to access to data via the Feelbat platform, the engineers at SID were able to establish a reasoned diagnosis, allowing them to rule out the hypothesis of a rapid or dangerous phenomenon.
This type of monitoring allows project owners to defer certain heavy operations while maintaining the ability to monitor and react quickly in the event of unforeseen developments.
Press contact
Impulse Communication Agency Paris
Marie Legrand – marie@impulse-communication.fr – 06 09 88 62 27
Julie Dalsace – julie@impulse-communication.fr – 06 78 70 96 05