Six-lane motorway links Mozart’s favourite towns

The A1 motorway is Austria’s main traffic artery, linking Salzburg – Mozart’s birthplace – with the capital of Vienna. Extremely high traffic volumes required the so-called “Westautobahn” to be widened to three carriageway lanes – and even to as many as six lanes on the section between Sattledt and the junction at Haid near Linz – in each direction. Over a total length of 19.7 km, this section of the A1 was expanded in concrete design.

The existing concrete pavement was used for the production of recycling granulate. A laser-controlled grader placed the material true to line and level, immediately followed by single-drum compactors of the 3000 series fitted with VIO drum which compacted the recycled mix. The VIO technology enables them to work with either oscillation or vibration. Working on the A1, they used the benefits offered by oscillation. This type of dynamic compaction is capable of achieving high degrees of density very quickly, therefore requiring fewer roller passes.

Where the existing construction materials lacked bearing capacity, the contractors decided to rely on a tried-and-tested system solution offered by Wirtgen: soil improvement using the soil stabilizer and cold recycler WR 2500. The WR 2500 recovered the existing material in 2.80 m long and just under 2.50 m wide sections each, adhering to the specified working depth of 20 cm with pin-point accuracy. The material was mixed with pre-spread cement and precisely metered quantities of water, all in one single machine pass. The water was fed into the soil stabilizer’s mixing chamber from a water tanker truck.

At an advance speed of between 15 and 20 m/min, the WR 2500 was operating in the lower range of its performance capacity. A powerful diesel engine provided the power needed by the 32-ton machine. Despite being a heavyweight, the recycler impresses with exceptional agility in repositioning and turning manoeuvres, which is owed to its finger-light hydraulic all-wheel steering.

Job site: A1 motorway, Austria

Project length: 19.7 km

Machines used

Wirtgen soil stabilizer WR 2500

Hamm compactors with VIO drum

Getting the job done with pin-point accuracy.

JOB REPORT - Asphalt paving

Paving asphalt with the NAVITRONIC® Plus 3D control system

The 1.2 km long section of the new road with several tight bends serves to bypass the village of St. Leon-Rot near Heidelberg, reducing the amount of through traffic. Among golf players, the village is known for its golf course, which hosted the “Deutsche Bank / SAP Open” from 1999 to 2002 and has also repeatedly been a venue for the European Golf Championship.

Using the NAVITRONIC® Plus control system was just the right solution on this section of the new road because – as is the case for most new construction projects – the design data were available in digital form. The 3D control system from Vögele can use these design data, thus dispensing with the need for time-consuming surveying and preparation work that is typical of levelling with stringlines. The economic efficiency of the entire project was increased considerably as a result.

The Super 1900-2 enabled the entire carriageway to be paved at widths between 7.60 m and 7.80 m in one single working pass. Because of the large working width, two receivers were mounted at the left and right screed arms respectively to establish the screed’s position, as well as grade and slope. Tight bends with radii of merely 400 m and varying cross-sections with slopes of up to 8% posed a particular challenge in this construction project. The steering operation was also governed by the NAVITRONIC® Plus system.

For control of the paving operation, NAVITRONIC® Plus requires the digital design data to be stored in a system computer on the paver. During the paving operation, a positioning system determines the current position of the screed with pin-point accuracy. The NAVITRONIC® Plus system continuously matches the measured results with the design data. As soon as the system identifies any deviation, the system computer automatically forwards the commands to adjust the paver’s steering and height adjustment.

The automatic system enabled the paver operator to fully focus on the paving operation and feeding of the paver with asphalt mix. There was not one single situation that required manual intervention into the paver’s automatic steering function. The screed operator needed to merely keep an open eye on the paving results, as both the paving width and the grade and slope were controlled fully automatically by the 3D system.

Job site: bypass L546 near St. Leon-Rot

Project length: 1.2 km

Bend radius: up to 400 m

Cross slope: up to 8%

Paving details

Material (base layer): bitumen-coated gravel

Width: 7.60 m - 7.80 m

Layer thickness (base layer): 12 - 16 cm

Paving speed: 3.5 m/min

Machines used

Vögele paver Super 1900-2

Vögele paving screed AB 600-2 TV

Vögele levelling technology NAVITRONIC® Plus

A2 motorway Austria

JOB REPORT - Asphalt compaction