A prestigious project that relies on Cometto self-propelled vehicles for its completion.
Where cars and trucks usually rush along the six-lane motorway, on this evening all traffic comes to a standstill. The total closure between the Bettembourg and Gasperich interchanges is necessary to bring the gigantic structure into position. With a length of 200 meters and a width of 18.5 meters, the arch spire reaching 40 metres from the deck to the highest point of the upper arch, it is one of the largest bow-string railroad bridges in Europe," Rui Raimundo, project manager at CFL, describes the impressive key figures.
Expansion of Luxembourg's rail network
Since 2020, expert technicians have been assembling the many individual parts of the tying chords, including the deck and the two double arches, on site. The result was the arch bridge with a weight of 5,850 tons. "This bridge is one of eight structures that will be built as part of the new railroad line between Luxembourg City and Bettembourg," says project manager Raimundo, citing the ambitious scope. "The new project is part of CFL's ambitious expansion and modernization program. Alongside the existing line, this supplementary line represents a significant capacity gain for this heavily travelled section of the Luxembourg rail network."
90 SPMT-axle lines on both sides
Hydraulic presses were used to gradually raise and align the structure in advance to a height of five meters to the level of the bridge bearings using the "pack & jack" method. Modular self-propelled vehicles, which are predestined for such heavy-duty tasks, are deployed for the final journey. The globally active specialists from Sarens are responsible for carrying out this demanding transport task. They put together the vehicle combination in advance and meticulously prepared the procedure.
Under the eyes of scores of observers, shortly after midnight the starting signal is given for the shifting operation. A total of 180 self-propelled SPMT axle lines are involved in this project, linked together as a 5x18 axle line combination at either end of the bridge.
Cometto modules provide optimum conditions
The bow-string bridge fits into the gap above motorway 3 with millimetre precision. Despite its impressive dimensions, it must be perfectly adapted to the future alignment of the new line. Due to the electronic steering, the SPMT units can be controlled precisely, everything runs according to plan in the darkness of the night. The LED lighting on the Cometto modules creates the ideal conditions for the operator. The stroke lets the convoy move forward safely and also compensates for bumps in the ground.
The mission is completed after about two hours and the 5,850-ton structure is set down on its final supports. The "bridge of superlatives" fits into Luxembourg's rail network as another jigsaw piece and now stands ready for the passage of trains.
Date of publication: 11/2022