Public Works has conducted additional inspections of bridges and viaducts following the collapse of the Carolabrug in Dresden, Germany, on September 11, 2024. Hydrogen embrittlement was identified as the main cause. Research by Public Works shows that there is currently no acute safety risk.
A second opinion, conducted by TNO, TU Delft, and TU Eindhoven confirms this conclusion. Ultimately, the affected bridges and viaducts will be replaced with priority.
What is Hydrogen Embrittlement?
Hydrogen embrittlement is a process where small cracks form in steel. This can occur in certain types of steel used as reinforcement in concrete in the 1950s and 1960s. Due to hydrogen embrittlement, the reinforcement can lose its strengthening function and weaken the structure.
Dutch Bridges and Viaducts are Safe
Following the incident in Dresden, Public Works conducted research on its bridges and viaducts. Public Works submitted its research for a second opinion to TNO, TU Delft, and TU Eindhoven. The second opinion confirms Public Works conclusion: the safety of our bridges and viaducts is not at risk. There are currently no management measures needed, such as placing support structures or limiting traffic.
Active Monitoring
The research results in 5 recommendations to maintain a good overview of the situation and potential safety risks: inspection, monitoring, determining steel type, additional numerical assessment, and strengthening the bridge or viaduct if necessary. Public Works follows these recommendations.
Public Works also maintains contact with Germany on how they have been handling the approximately 700 bridges that may be susceptible to hydrogen embrittlement since the collapse.
Overview of Bridges and Viaducts
Public Works manages 13 bridges and viaducts where the type of steel possibly susceptible to hydrogen embrittlement has been used. However, the steel processing method involved in the German Carolabrug was different. The following bridges and viaducts are involved:
| Object Name | Location |
|---|---|
| J.F.Kennedyweg | Over A16 Rotterdam |
| Steenenhoek Oost | In A27 near Gorinchem |
| Steenenhoek West | In A27 near Gorinchem |
| Cadettencamp Oost | In A27 near Breda |
| Cadettencamp West | In A27 near Breda |
| Spoorviadukt Noord | In A67 near Geldrop |
| Spoorviadukt Zuid | In A67 near Geldrop |
| Oosterhoutse Brug Noord | In A27 near Oosterhout |
| Oosterhoutse Brug Zuid | In A27 near Oosterhout |
| Rozendaals viaduct - East | In A12 near Arnhem |
| Rozendaals viaduct - West | In A12 near Arnhem |
| Algerabrug | Bridge SVK Hollandsche IJssel |
| Kleinpolderplein | In A20->A13 Rotterdam |
The mentioned bridges and viaducts are safe to use. If Public Works cannot guarantee the safety of an object, it will be closed off.
Part of a Larger Renewal Task
Ultimately, the affected bridges and viaducts of Public Works will be replaced. The replacement of these objects is part of the larger Renewal Task of Public Works. In this task, Public Works will tackle hundreds of bridges and viaducts in the coming years.
Parliamentary Letter
The House of Representatives has been informed about the research findings through a parliamentary letter.