Corrosion fatigue collapse: lessons from the toll gantry

Published on 2026-07-02 | Translated from Spanish

Last March, a toll highway sign gantry collapsed due to a fracture at the base of a column. The investigation determined that the cause was corrosion fatigue, triggered by the accumulation of de-icing salts. This case reminds us that visual inspection is not always sufficient.

Photorealistic engineering visualization of a collapsed highway toll gantry column base, fractured steel surface showing corrosion fatigue crack propagation, orange rust stains and salt deposits accumulating at the foundation joint, a technician in safety vest using a handheld ultrasonic flaw detector to scan the broken metal while a laptop with structural analysis software displays stress concentration contours, heavy rain falling on the scene, wet asphalt reflecting dim industrial lighting, broken bolts and metal fragments scattered on the ground, dramatic low-angle shot emphasizing the sudden structural failure, ultra-detailed metallic fracture surface with granular texture, cinematic technical documentary style, high contrast between dark steel and bright corrosion areas

Pipeline 3D: from point cloud to forensic analysis 🛠️

To document the collapse, a FARO laser scanner was used, processing the data in FARO Scene. The resulting point cloud was exported to Autodesk ReCap for cleaning and registration. With this model, it was possible to accurately measure the fractured section and simulate accumulated stresses. The workflow allowed experts to calculate the remaining service life and confirm that stress corrosion was the determining factor in the failure.

The salt that binds us: when de-icing gets personal 🧂

De-icing salts have a special knack for getting where they are not invited. In this case, they accumulated at the base of the column for years, creating a perfect environment for corrosion. The gantry held on stoically until it had enough. Perhaps we should consider that, just like in relationships, the accumulation of small unresolved problems eventually brings everything down.