The 940 metre long temporary bridge is now more than just a steel structure. It is the result of 2,000 metres of longitudinal girders and 3,500 metres of cross girders, which were manufactured in three different steelworks. More than 100 lorry loads were needed to deliver the massive components. Joining the parts required an impressive amount of welding work - a total of 28 kilometres of weld seams. Where welding was not used, bolted connections were utilised, particularly for almost all of the 351 cross beams. Given the weather conditions in Hanover, where around 672 litres of precipitation fall per square metre every year, comprehensive corrosion protection was essential.
Concrete construction completed
While the steel construction was celebrating its so-called "wedding" with the insertion of the last cross girder, the concrete construction was running at full speed at the same time. Once the steel structure was complete, the prefabricated parts had to be placed exactly on top of the steel girders. This required maximum precision: the connecting reinforcement of the prefabricated parts had to be threaded between the head bolts of the steel girders with millimetre precision. The last of almost 2000 precast elements was laid at the beginning of August.
Once the prefabricated parts have been completely laid on the supporting structure, the ironworker comes into action and uses wire and pliers to "thread" all the individual bars together to form a rigid reinforcement body. In some cases, this involves weighing more than 360 kg per cubic metre of concrete. The concreting sections of the individual supporting structures are between 50m3 and 250m3. This corresponds to around 7 to 35 fully loaded concrete lorries. More than 3/4 of the superstructures have already been concreted. The concreting of the caps on the superstructures marks the end of the structural work on the steel composite structure and is a prerequisite for the subsequent work on the railings and noise barriers. This is followed by the two-layer asphalt paving on the concrete of the superstructure as well as the marking work and the installation of the guiding elements. After the main bridge inspection, nothing stands in the way of commissioning.
Intelligent construction connects
The completion of the steel construction is not only a technical success, but also a triumph for the consortium, the client and all those involved in realising this project with their expertise and passion. It is proof that even the greatest challenges can be mastered with shoulder-to-shoulder cooperation, expertise and precision.
We are now on the home straight to the completion of the temporary structure. The inauguration of the bridges is within sight.