‘Moving a 106-year-old bridge has its challenges,' says Arjan Bossers, project manager at Wagenborg Nedlift. 'The bridge was at the end of its life. This means that the structure might not be reliable in all respects. It was therefore important to use the right method to safely remove the central part of the bridge.
To do this, we built two large container support structures on our SPMT trailers. The supported SPMTs were positioned on a coupled pontoon from our colleagues at Wagenborg Towage. This enabled us to navigate under the middle section of the bridge. In addition, our lifting team lifted the abutment bridges with the 500-tonne and 700-tonne mobile cranes prior to removal.’
Then came the exciting moment: removing the bridge from its abutments. ‘Fortunately, the dismantling specialists had already made the necessary preparations for this,’ continues his colleague Alwin Schuitema, supervisor and operations manager for this project.
‘Using the trailer hydraulics and a ballast operation with the pontoon, we easily lifted the bridge off the abutments and then turned it 90 degrees. The JS250 box jacking system was then used to lower the bridge 10 meters so that it was at working height on the pontoon. It was then dismantled by the demolition contractor.’
The new railway bridge, a 110 meter long colossus weighing 900 tonnes, was already ready at the construction site next to the railway. 'Once the old bridge had been dismantled and removed, we set up the pontoon for the new bridge to be moved in. This was a completely different method to the dismantling process,' says Alwin.
'The first thing we did was to reassemble the JS250 jack-up system on the pontoon,' adds Jordy Batema, assembly worker. This handy and ergonomic system is very strong and a godsend for this bridge, which we jacked up to a height of 10 metres. Warre te Riet Scholten, engineer on the project: 'The new sliding system was installed on top of the jack-up system. We have developed this sliding system in-house with our own team of engineers to enable bridges like this to be inserted efficiently and safely.'
'The new sliding system is a great addition to our other bridge installation techniques and a real godsend for this project!'
Warre te Riet o.g. Scholten, engineer
Meanwhile, hard work was also carried out on the landside. Henrie van den Berg, transport supervisor: 'The SPMTs were used on the landside to manoeuvre the bridge. On top of the SPMTs we built the Modular Support System. And on top of that we installed our sliding system, or 'Verschubwippen' as they say in German.'
'We were busy for several days with the installation of the new bridge. In fact, it was done in several phases,' Arjan explains. The bridge had to be 'handed over' several times. The Wagenborg sliding system in combination with a set of strandjacks was essential for pushing the bridge over the canal. Finally, we placed the bridge on the abutments and the job was done.'
‘With a job as varied and complex as this one, we involve the whole team in the project at an early stage,' says Arjan. 'So Alwin and Warre took part in discussions with the client and made site visits. And Henrie gave his opinion on the transport solution proposed.
We take the experience and input of our field experts into account during the preparation phase, so the team is already attuned to each other before the job starts. This really pays off during the execution phase. And after a project is completed, we always do an internal project evaluation. Points for improvement are taken into account for subsequent projects. This is how we grow as a team and as a company.’
Arjan: 'How do I look back on this project? It was another great piece of teamwork from our professionals. The circumstances were certainly not easy with the extremely hot and sunny weather of the last few weeks.'
'Together they pulled together and made sure this challenging job went off without a hitch. An achievement I am proud of!'
Arjan Bossers, project manager