A45 bridge: Partial demolition successful at Siegen

The second part of the A45 viaduct Eisern near Siegen was successfully blown up on Sunday. Everything went according to plan. The structure fell to the side so as not to damage the other part of the bridge.

Exactly at 11 a.m. on Sunday, demolition expert Michael Schneider pressed the ignition button. After the loud bang, the second section of the Eisern viaduct fell to the side – as planned. The other part of the bridge, which is already newly built, was not damaged.

The blast went absolutely according to plan, as the demolition expert said shortly afterwards. Despite the rain, many onlookers came into the forest to watch the blasting of the viaduct from a safe distance.

Successful blast

After 56 years, the Eiserntal Bridge is now history. Apparently everything went according to plan, say those responsible on site. The other part of the bridge was not damaged either.

The team from the Technical Relief Agency cordoned off the area around the bridge on Sunday morning. Search dogs were also used to make sure everything went smoothly. There were no problems with the blocking, according to the demolition expert. The A45 is expected to be reopened to traffic around 2 p.m.

What happens after the blast?

After the blast, you have to clean up under the bridge. It will take several weeks before all the rubble from the blown-up bridge has been removed – probably by the end of May. Then the country road 909 between Eisern and Obersdorf, which runs under the bridge, should be passable again.

The second part of the structure in the direction of travel to Frankfurt is then to be rebuilt. According to Autobahn GmbH, the first vehicles should then roll over the new, completely finished Eisern viaduct in 2024.

Why was the bridge blown up?

The Eisern viaduct has become too small for the current traffic situation. That’s why Autobahn GmbH wants to expand the bridge from the current five to six lanes in the future. The two structures that make up the bridge had to be blown up to make room for the new building.

First, in October 2020, the first half of the bridge in the direction of Dortmund was blown up. After that, the new part of the structure was completed. At the end of February the Traffic transferred to this new structure.

What were the preparations for the demolition like?

Preparations for the blasting have been underway since traffic was diverted to the new part of the structure. Trucks unloaded earth and gravel below the bridge so that it could land gently in the valley when it was blown up.

The bridge also lost weight as the railings were dismantled and the asphalt layer removed. Not too many parts of the bridge had to fall down and the force of the impact was reduced.

In addition, master blaster Michael Schneider and his team drilled holes for the explosives – 525 drill holes had to be filled with a total of 45 kilograms of explosives.

So-called blasting mouths, which look like triangles, were cut into the pillars. Mouths were drilled into these and filled with charge. During the blast, the triangles flew out, so that each pillar and the bridge could fall sideways.

Why is the situation around the demolition of the Rahmedetal Bridge more complicated than here?

Because immense damage was discovered during an inspection of the Rahmedetalbrücke – since then it has been considered in danger of collapsing. This damage necessitated an immediate closure in December 2021.

Shortly after the closure, it became clear that the Rahmedetal Bridge could not be repaired. It needs to be demolished and rebuilt. In Germany, demolition and new construction of a motorway bridge are legally and bureaucratically complicated.

Source: wdr.de