Sarens Technical Solutions installs bridge in Nantes
Sarens Technical Solutions & Engineering is known for taking on any client challenge and delivering masterful results–especially with bridge installations, which are often complex yet time-sensitive operations.
Such was the case at one of Sarens’ most recent bridge installation projects, conducted on behalf of customer Bouygues Travaux Publics Régions France and owner VINCI Autoroutes, along the A11 highway in Nantes, France. The Sarens team came together in June of 2023 to successfully jack, transport, and install a 740-tonne, 110-metre long bridge along the A11 at the Portes de Gesvres interchange.
To do it, they deployed the following equipment:4 Kamag SPMTs, 6 axle lines each; 4 CS450 towers with 12 elements on one side; 4 CS450 towers with 10 elements on the other side.
The CS450, in particular, was chosen for its higher elements, which would allow the crew to jack down faster. This was especially important due to the project’s exacting time constraints: the A11 would be closed for only six hours during the night, giving the crew limited time to drive the SPMTs 70 metres and successfully jack down the bridge.
There were other challenges to contend with on-site, too: first, because the job site was located along the highway, it meant there would be limited space and access for vehicles and equipment. For example, only one truck was allowed to enter the work site at a time, requiring the crew to meticulously follow a precise transport schedule. The road itself was a challenge, as well: the crew would have to drive 70 metres across a highway that was angled in two directions, with up to 4.5% in one direction requiring maximum SPMT stroke.
As always, Sarens equipment, expert crew, and situational know-how made this operation a success. The necessary equipment arrived via 13 trucks from various locations around Europe, and the crew assembled the SPMTs and their transport structure within one day, thanks to a well-coordinated pre-assembly effort at Sarens HQ in Wolvertem.
Next, it was time to jack-and-pack the 740-tonne curved bridge, jacking it from 1,5 metres to 4 metres high. From there, the CS450s took over. Positioned on top of the SPMTs, they lifted the bridge at an angle of 5% along its width, transporting it over 70 metres of highway. Finally, the crew jacked it down two metres onto its final supports–all within the brief 6-hour timeframe!
Sarens is proud of the team that made this possible, especially the project team, engineers, and eight on-site crew members who worked with precision and skill to make this installation a success. Thank you to everyone involved in this fantastic project.
