Construction of the Viaduc de Millau – the tallest and longest cable-stayed road bridge in the world – took no more than three years. The bridge was opened to traffic in 2004, being part of the A75 motorway section between Clermont-Ferrand and Béziers, close to the town of Millau.
Taking the motorway from Paris to Southern France, drivers now cross the gorge of the river Tarn at a height of 270 m, which not only avoids endless traffic jams but saves many miles on the way as well.
When work on the steel construction of the impressive bridge structure had been completed, a SUPER 1900 road paver from Vögele commenced paving the asphalt carriageway. Highly elastic asphalt material with a high polymer content was used, offering maximum resistance to possible deformations of the bridge’s steel body caused by strong winds or temperature fluctuations.
A 3 m wide hard shoulder, two traffic lanes of 3.50 m width each, and a 1 m wide boundary were paved in each direction over a total length of 2.5 km. Altogether, the Super 1900 from Vögele used some 9,500 tons of asphalt. The paving operation was completed in no more than three days.
The use of static rollers had initially been considered for compaction of the 8 cm thick asphalt layer, as the bridge’s steel construction precluded the use of vibration rollers. The group of firms responsible for the project’s structural implementation could be convinced, however, of the exceptionally effective dynamic compaction with oscillation offered by Hamm.
This led to a DV 90 VO tandem roller from Hamm being used, which compacted the special asphalt successfully with oscillation – dynamically, yet without causing damaging vibrations. Compaction of the pavement had to be completed within a short time frame, as strong winds on the bridge caused the asphalt to cool down quickly. Yet another advantage of oscillation now became apparent: Oscillation rollers achieve the specified density much more quickly, because their drums maintain permanent contact with the ground. In view of that, the asphalt pavement on the Viaduc de Millau was compacted very gently, yet without difficulty even after the asphalt temperature had dropped.