It's a mammoth project: Current plans foresee the complete renovation and modernization of the Mont Blanc Tunnel over its full length of almost 12 km by 2042.
Working on the project are two wheeled pavers from Vögele — a latest-generation SUPER 1803-5 X and a SUPER 1303-3i.
Around 2 million vehicles a year travel through the Mont Blanc Tunnel. Since the 1960s, the tunnel has linked Chamonix in France to Courmayeur in Italy, making it one of the most important north-south corridors in the European road network.
Over almost the next two decades, the infrastructure is to be modernized in stages, and the safety technology will be brought up to date. However, since the tunnel is of the utmost importance for tourism on both the French and Italian sides, it can only be closed for a few weeks — and countless nights — at a time.
As part of the project, contractor Cogeis SpA was commissioned to carry out extensive resurfacing work on a 400 m section of the tunnel. This was a challenge, as tunnel sites mean confined spaces, darkness, restricted visibility, strict safety requirements and a tightly scheduled project timeline.
In just one night, the aim was to pave the entire section with a 5-cm surface course across a width of 6.5 m. In cases like this, everything depends on efficient machine technology, so the contractor chose to use a latest-generation wheeled paver from Vögele, the SUPER 1803-5 X.
With a laydown rate of up to 700 t/h, this representative of the Universal Class is Vögele's most powerful wheeled paver and can pave widths of up to 8.25 m. This enabled the paving crew to use the SUPER 1803-5 X for the seamless paving of both carriageways in a single pass.
Its agility also played an important role, as its Pivot Steer steering brake reduces its turning circle to just 4.2 m, enabling it to maneuver with ease, even in the narrow tunnel. It was backed up by its "little brother," the SUPER 1303-3i: This Compact Class paver allowed the paving crew to pave three emergency parking and breakdown bays with a length of 150 m and a width of 2.8 m parallel to the two-lane carriageway.
The technologies of the new "Dash 5" generation brought several advantages on this tunnel project, including, among other things, the new automatic and comfort functions of the SUPER 1803-5 X.
The convenient Paver Access Control (PAC), for example, was a great help to the crew when starting up and shutting down the paver.
The crew was able to use the control unit on the screed to control all initial steps from the ground just by pressing a series of buttons: turning on the lights and starting the engine, putting up the hardtop, lowering the screed and booting up the machine control system. It enabled operators to switch on the integrated lighting in the dark tunnel and start preparing for work at once.
The optional Light Package Plus of the "Dash 5" paver was a great help in the Mont Blanc Tunnel in more ways than one.
Apart from being easy to activate without any installation effort or setup time, the new lighting system provided optimal illumination: The package contains additional integrated LED lights in the hardtop and in the cross-member of the control panel, illumination of the tow point rams, freely positionable headlights and a special hardtop extension with powerful LEDs. These evenly illuminate the working area to a width of up to 10 m and up to 4 m behind the screed.
"This enabled us to set up and prepare the paver quickly without the need for additional lighting and then work in ideal lighting conditions," said Lori Bibe, paver operator at Cogeis SpA.
Another benefit in the Mont Blanc Tunnel: The SUPER 1803-5 X has a drive concept that significantly reduces both fuel consumption, carbon emissions and noise. The major role here is played by the improved EcoPlus low-emissions package. This reduces fuel consumption and, in combination with other measures, cuts noise emissions.
The latest-generation AB 500 TV extending screed also works with lower noise levels than before.
"These factors are critical, especially in narrow, enclosed spaces like the construction site here in the tunnel," foreman Antonio Lachi said.
The new installation aid for bolt-on screed extensions and the efficient heating of the compacting systems also help to minimize the set-up time.
"The new extending screed is very user friendly and saved us a lot of time here," Lachi said.
In combination with the optimized material management, which ensured a consistent supply of material and an ideal head of material in front of the screed, the paving crew achieved a high standard of paving quality. All of this occurred despite the tight deadlines and the asphalt having to travel for around two hours in winter temperatures.
The Mont Blanc Tunnel shows just what the "Dash 5" generation can achieve in day-to-day situations: more convenience, simple operation and greater efficiency when paving.
