Scanning Tunnels

Structural Repairs Assists Rail Operators in Scanning Tunnels with Ultrasound and GPR Technology

Structural Repairs, a renowned UK-based company specialising in advanced non-destructive testing (NDT) techniques, has been helping rail operators effectively scan their tunnels using Ultrasound Thickness Testing (UTT) and Ground Penetrating Radar (GPR).

By leveraging these state-of-the-art technologies, Structural Repairs empowers rail operators to proactively identify potential issues and make data-driven decisions regarding tunnel maintenance and repairs.

The Challenge

Rail operators face the daunting task of maintaining the structural integrity and safety of their tunnels, which are continuously exposed to various stresses such as ground movement, water infiltration, and the impact of passing trains.

Over time, these factors can lead to deterioration, including cracks, voids, and thickness reduction in tunnel linings. Identifying these issues early is paramount to preventing further damage and ensuring the smooth operation of the railway network.

The Solution:

Structural Repairs partners with rail operators to implement a comprehensive tunnel scanning strategy using UTT and GPR technologies.

UTT is employed to measure the thickness of tunnel linings, enabling the detection of any areas of reduced thickness that may compromise the tunnel's strength. Simultaneously, GPR uses high-frequency radio waves to generate detailed images of the tunnel's subsurface, unveiling hidden voids, cracks, and water infiltration.

By combining the data obtained from UTT and GPR scanning, Structural Repairs provides rail operators with a holistic understanding of their tunnel's condition.

The GPR data is processed to create 3D models of the tunnel, precisely identifying the location and extent of any anomalies.

The UTT measurements are then superimposed onto these models, offering a comprehensive overview of the tunnel's structural health.

The Result:

The collaboration between Structural Repairs and rail operators has yielded impressive results in identifying potential tunnel issues. In a recent project, a rail operator sought Structural Repairs' expertise to assess a railway tunnel exhibiting signs of deterioration. Utilising their advanced scanning techniques, Structural Repairs detected several areas of reduced lining thickness and a significant void behind the tunnel wall that had previously gone unnoticed during visual inspections.

Equipped with this valuable information, the rail operator took swift action to repair the affected areas and fill the void, preventing further damage and ensuring the safe operation of the railway line.
This proactive approach, made possible by Structural Repairs' UTT and GPR scanning services, averted a potential tunnel collapse and minimised disruption to the railway network.

Structural Repairs' collaboration with rail operators, utilising UTT and GPR scanning technologies, has transformed the way railway tunnels are assessed and maintained.

By providing rail operators with accurate and detailed data on tunnel condition, Structural Repairs enables them to make informed decisions and prioritise repair work.

Their dedication to leveraging cutting-edge NDT technologies has positioned them as a trusted partner for rail operators seeking to ensure the safety and longevity of their tunnel infrastructure.


If you are a rail operator responsible for the management and maintenance of railway tunnels, partnering with Structural Repairs can help you stay ahead of potential issues.

Contact Structural Repairs today to discover how their UTT and GPR scanning services can assist you in maintaining the integrity and safety of your tunnel network.

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