Infrastructure failures rarely occur without warning. However, early signs of deterioration are often missed, and damage is only identified when intervention becomes urgent or unavoidable.
Recent advances in sensing and data analytics are enabling a transition from periodic inspection regimes to continuous, data-driven structural monitoring.
At the University of Luxembourg, Prof. Numa Bertola and his team are contributing to this shift by developing advanced sensing approaches, improving the way infrastructure is monitored.
From inspection-based assessment to continuous monitoring
Current infrastructure management practices rely largely on periodic visual inspections combined with simplified analytical models. While well established, this approach remains subjective and inaccurate.
Implementing sensors on the bridge enables continuous monitoring of structural behaviour over time, under real operating conditions. “This improves the ability to detect early-stage anomalies, reduces uncertainty in condition assessment, and supports more informed maintenance planning,” explains Prof. Numa Bertola.
A novel sensing technology is currently validated in operational environments, such as on the Ferpècle bridge in Switzerland. The next development challenge lies in integrating high-resolution data streams into standardised workflows that can support decision-making at scale.
How does it work?
The research is based on distributed fibre optic sensing technologies applied directly to full-scale infrastructure.
These systems measure strain at the millimeter-scale resolution along structural elements. On a 35-metre bridge, this corresponds to approximately 11,000 measurements points, compared to only a handful of measurement locations in conventional sensor devices.
This level of spatial resolution enables a more detailed understanding of structural behaviour under real loading conditions, including the identification of localised effects such as cracks that would otherwise remain undetected.
Economic and operational value for asset owners
For infrastructure owners, the primary value proposition lies in the management of life-cycle optimisation.
Structural health monitoring allows interventions to be planned based on actual structural conditions rather than assumptions. It also extends the service life of existing assets, reduces the frequency of invasive inspections, and optimises maintenance timing and scope. Given the small cost of monitoring compared to maintenance cost, monitoring activities can bring significant economic benefits to asset managers.
In several cases, monitoring results have revealed additional reserve of load-bearing capacity. “One instrumented bridge was found to perform approximately 20% better than initial estimates suggested,” states Prof. Bertola. By providing concrete data that proves the structure’s continued good health, we can not only save significant amounts of money but also avoid unnecessary interventions, limiting our environmental impact.
Application domains
The technology is particularly relevant for organisations managing large, safety-critical infrastructure portfolios with long-term performance requirements.
This includes public infrastructure authorities such as Ponts et Chaussées, railway operators such as CFL, and asset managers responsible for bridge and tunnel networks, where improved condition assessment and risk control are key priorities.
Engineering consultancies are expected to play an important role in integrating these monitoring approaches into existing assessment and maintenance workflows as they become more standardised.
“Beyond bridges, the technology is directly transferable to tunnels, retaining structures, industrial slabs, and energy infrastructure, where structural degradation is slow, distributed, and difficult to assess using conventional methods.” – Prof. Numa Bertola.
Industrial collaboration and technology transfer
The research is closely aligned with industrial deployment through collaborations with infrastructure owners and specialised monitoring companies, including Swiss bridge monitoring spin-offs such as SwissInspect and IRMOS Technologies.
It also builds on partnerships with leading fibre optic sensing technology providers like Luna Innovations and Smartec, which supply the underlying measurement systems used in field deployments.
While no dedicated spin-off has yet been formalised around the data analytics layer, this remains a key area for future industrialisation, particularly in the development of decision-support tools that translate raw sensor data into actionable engineering insights.
In this context, the next phase of development will focus on scaling these solutions and integrating them into standard engineering and asset management practices. As adoption progresses, structural health monitoring is expected to play an increasingly central role in improving the reliability, sustainability, and cost-efficiency of critical infrastructure systems.