Hundreds of German bridges may need to be replaced because they contain endangered high-strength steel, a survey by the business magazine “Capital” of the transportation ministries of the states has shown.
According to the evaluation, at least 534 bridges have high-strength steel that is at risk of stress corrosion cracking, a type of damage that has been known to cause the collapse of bridges. The recent collapse of the Carolabrücke in Dresden, which occurred last September, is believed to have been mainly caused by this type of damage.
The largest number of bridges with corrosion-prone high-strength steel, as expected, can be found in the most populous federal state of North Rhine-Westphalia, with 100 potential affected structures. In Baden-Württemberg, there are 73 and in Brandenburg, 71.
In addition to the bridges under state jurisdiction, there are also those under federal responsibility, although the Federal Ministry of Transport has not yet included these in its assessment.
Steffen Marx, a professor at the Institute of Structural Engineering at the Dresden University of Technology, estimates that at least 1,000 bridges across the country are potentially affected. High-strength steel bridges are not inherently at imminent risk of collapse, but there is a risk that microscopically small cracks can form, which can grow over time and eventually lead to a collapse. Most of the federal states therefore intend to conduct more thorough inspections of potentially affected bridges and replace them in the long term, according to the transportation ministries cited by “Capital”.