Checking the load-bearing structure of a road bridge with photogrammetry
Many road bridges in Romania were built decades ago and have received little maintenance, and their safety depends on an accurate assessment of the load-bearing structure. Photogrammetry offers a modern way to measure and report a bridge’s condition: images processed into a 3D point cloud yield precise information about the surface and geometry of the structure. This article explains how the load-bearing structure of a road bridge is checked with 3D technology and what its rehabilitation involves.
Methods for checking the load-bearing structure
To establish whether the bridge structure is affected and to what extent, a cadastre and topography company can identify, measure and report its condition for analysis.
Among the available methods, the most modern fall under photogrammetry. It relies on images captured on site and processed as a 3D point cloud, from which precise information about the measured surface is derived. Photogrammetry can be carried out either with drones — flying over the target and photographing it — or with the classic method, using a camera. The results include orthophotos with geotechnical data and digital terrain models.
How a bridge with a damaged structure is rehabilitated
If the analyses show that the bridge structure is affected, traffic may need to be restricted or temporarily closed. Architects and engineers then draw up the rehabilitation plan:
- Soil analysis — the structure and composition of the ground indicate how solid it is to support the bridge’s weight.
- Identifying the affected elements — exactly which components are deteriorated is established.
- Choosing rehabilitation methods — depending on the technical condition, the appropriate techniques are selected.
All decisions are made after a thorough analysis, with the aim of bringing the bridge back to safety and comfort parameters so it once again becomes usable, durable and safe.
Conclusion
The 3D technology used by photogrammetry is one of the most modern methods for assessing infrastructure, and the information obtained is highly accurate. For photogrammetric inspection of a bridge or a load-bearing structure, contact us.