Floating crane helps dismantle 320-tonne bridge

The onshore crane and barge mounted floating crane working together to remove a section of the A43 bridge. (PHOTO: Autobahn GmbH)

Essen-based contractor Heitkamp Industrial Solutions recently removed the 320-tonne eastern part of the ageing A43 bridge, on behalf of motorway operator Die Autobahn GmbH. 

The works are being carried out as part of the expansion of the A43 between Marl and Wittento - one of the most important construction projects in the region.

Heitkamp worked with crane company HKV Schmitz and experts from heavy lifting specialist Hebo Maritime Service to cut and lift out the eastern side of the bridge.

Two cranes were employed to facilitate the manoeuvre; one situated on the bank of the canal and a second, the Hebo-Lift 8 barge mounted crane, floating on the canal.

Hebo-Lift 8’s lattice boom slewing crane lifts 300 tonnes at a radius of 15 metres. Its maximum lifting height is 44.46 metres.

The 300 tonne capacity floating crane holds the weight of the larger bridge section while the onshore crane hoists a smaller section away. (PHOTO: Autobahn GmbH)

Carola Ziebs, North Rhine-Westphalia State Road Construction Agency’s project group manager for the expansion of the A43, said: “This is a milestone in one of our most demanding construction projects that we currently have to offer in the region. The demolition was a real challenge.”

According to Carola, the bridge had to be strengthened prior to its dismantling to allow the western half of the structure to accommodate road traffic, while the eastern half was removed prior to rebuilding.

While the eastern part of the structure was provided with an undertension, the roadway of the western half of the bridge was reinforced with a high-strength concrete slab - the first time this reinforcement method had been used in North Rhine-Westphalia - to ensure it would withstand the additional load stresses during the dismantling.

The eastern bridge section was then lightened by removing “as many steel parts as possible”.

The floating crane hoists the eastern bridge section ashore. (PHOTO: Autobahn GmbH)

Speaking of the dismantling work, Autobahn said: “The excavation of the bridge itself was unusual: the 320-ton eastern half was cut in two.

“The larger part of the bridge was spectacularly swung to the north shore with a special floating crane. For the smaller part, a classic crane was used on the south bank.”

Carola added: “Otherwise, we would have had to push the bridge over the highway. This would have required reinforcements, shipping on the canal would have been significantly restricted and we would have needed a few months longer.”

Demolition workers on an access platform cut the A43 bridge into sections. (PHOTO: Autobahn GmbH)

The A43 bridge is one of three bridge structures over the Rhine-Herne Canal. Collectively known as the “Emschertal Bridge Train”, the motorway bridge and its two adjacent railway line bridges are all to be dismantled and their replacement structures built and installed at almost the same time.

“These bridges have to be built together because of their physical proximity,” said Carola.

“As a north-south connection, the A43 is the artery of the eastern Ruhr area. We have to be creative and innovative here in order to reconcile the demands of all modes of transport on rail, water and motorways.”

According to Autobahn, the replacement structure for the A43 motorway bridge is currently being pre-assembled to the south of the existing bridge, and will be installed in the coming weeks.