Construction defects: Thousands of bridges need to be checked

In mid-June, the Salzbachtal bridge near Wiesbaden suddenly sagged by half a meter – due to a broken component. According to research by Report Mainz Thousands of bridges now have to be examined.

After research by the ARD-Political magazine Report Mainz Autobahn GmbH is currently checking the condition of the so-called roller bearings on thousands of bridges across Germany. This emerges from a verbatim protocol of the transport committee of the Hessian state parliament from July 2nd, the Report Mainz is present.

The trigger for the investigation is the breakage of a roller bearing on a pillar of the Salzbachtal bridge on Autobahn 66 near Wiesbaden. The breakage of the camp on which the superstructure of the bridge lay led to the bridge sinking by around half a meter on June 18, severely damaging one of the bridge piers. The bridge has since been considered extremely vulnerable to collapse and is closed, as are the roads and rails below.

With the Germany-wide investigations, one wants to rule out that the storage type is part of the problem, said Alexander Pilz from Autobahn GmbH to the transport committee. “The only thing that is clear is that the bearing has virtually failed, but whether the failure of the bearing is the real cause is part of the investigation.” Upon request from Report Mainz the Hessian Ministry of Transport confirms the inspections. The Autobahn GmbH has started a “nationwide test of structurally identical roller bearings.” This should be completed by the end of August.

“Spontaneous Failure” in 1960s Bridges?

It has been known for many years that the Salzbachtal Bridge has to be demolished and rebuilt. At a meeting of the transport committee of the Hessian state parliament on December 16, 2020, Transport Minister Tarek Al-Wazir (Bündnis 90 / Die Grünen) named the Salzbachtal bridge as one of three very special “problem bridges in the motorway area”. He also mentioned the Berghaus bridge the A44 between Kassel and Dortmund and the Thalaubach bridge, which is part of the A7 near Fulda. He was told that this bridge tended to “fail spontaneously.” When he asked what that meant, he became “completely different,” said Al -Wazir literally: “Spontaneous failure means the break occurs and the bridge just collapses.”

According to the protocol, ministerial director Martin Weber from the State Ministry of Transport in Hesse sees a general problem with older prestressed concrete bridges: “There are some constructive peculiarities of the bridges of the sixties that the constructions of the time have this problem what Minister Al-Wazir has just mentioned lies in the construction. ” You have to imagine it as if you were pulling a card out of a house of cards. Modern bridges, on the other hand, have a “high toughness”. You wouldn’t collapse immediately if a support buckled.

Chunks of concrete fell on the pavement

The Salzbachtalbrücke is an important traffic junction in the Rhine-Main area. The motorway bridge consists of a north and a south structure. The southern part has not been used since 2019. Under the bridge, however, traffic continued on a busy federal road and the railway line to Wiesbaden Central Station.

On the afternoon of June 18, 2021, passers-by noticed that concrete parts were falling from the bridge. One of the eyewitnesses is the 28-year-old Wiesbaden Wulf Goretzky. Report Mainz was with him at the locked bridge. On site he describes what he saw. He noticed a cloud of dust and then looked up at the bridge pillar: “After three or four seconds, chunks suddenly came down. In terms of size, I would say fist-size. Many landed on the roadside and one actually landed on the roadway.” He immediately informed the police. Since then nobody has been allowed to approach the bridge, life is in danger.

Opposition speaks of control failure

The Salzbachtal Bridge was also a topic in the Hessian state parliament on July 8th. The opposition accuses the black-green state government of failing to monitor the bridge. In 2019, 14-day routine checks on the south bridge were suspended after it was closed to traffic. “That was negligent,” criticized the transport policy spokesman for the FDP in the state parliament, Stefan Naas. He also sees mistakes in the Hessian Transport Minister Tarek Al-Wazir: “He is the employer of Hessen Mobil. He should have made sure that this is monitored much better here and that you take a closer look and that you maybe check more than once too little, “says Naas Report Mainz.

Janine Wissler (Die Linke), Chairwoman of the Transport Committee in the Hessian State Parliament, explains in an interview with Report Mainz: “It is a different matter if it becomes apparent during an inspection that parts are loose or if passers-by have to call the police because concrete parts are falling.” The sagging of the Salzbachtal bridge is an “absolute alarm signal” for them, because the bridge stands for a type of motorway bridge that was often built in this way in the 1960s. That is why she sees a nationwide problem and calls for the construction of the bridges to be checked for defects and weak points.

When asked why the damage to the bridge was not noticed by systematic controls, the Hessian Ministry of Transport explains that the sudden sagging of the superstructure of the bridge was noticed by both employees of the construction company and passers-by. As a result, the road and railway line were immediately blocked. The south bridge was no longer checked regularly because it was no longer used. It was not to be expected that the superstructure of the bridge could sag.