A4, Landkreis Bautzen

On behalf of Die Autobahn GmbH des Bundes, the consortium consisting of the Berlin transport route engineering branch and the PORR subsidiary G-S Straßenbau renewed the road surface on the A4 Aachen - Görlitz motorway between the Ohorn and Burkau junctions. Over a length of 4,310 m and a width of 11.50 m, a surface course of MA 8 S mastic asphalt was laid on the Aachen carriageway using viscose-modified bitumen 25/35 VL as well as a proportion of Trinidad Epuré (TE) natural asphalt. The paving thickness is 3.5 cm, the asphalt density 2.450 t/m³.

On-schedule completion under difficult conditions

As the mastic asphalt layer was produced using a sprocket screed, 50 cm wide mastic asphalt strips were built in the edge areas before the actual asphalting work began. Roof battens were used to stabilise the edges. The actual surface course was produced in two phases with widths of 5.4 metres and 5.1 metres. Due to the self-compacting properties of the viscous material, additional rolling was not necessary.

To improve the skid resistance of the surfaces, a lightly bituminised, crushed aggregate was then spread in accordance with method B of the ZTV asphalt regulations at a composition of 11 kg/m² 2/4. Despite the challenging conditions - the paving width from the edge of the carriageway to the safety barrier, including all work areas, was only 7 m - the construction work was completed within a very short time.

Properties of mastic asphalt bring economic benefits

High-quality durability and watertightness are two of the special properties of mastic asphalt. Due to its impermeability, the material is able to withstand the heaviest traffic loads far longer and better than conventional Rolled asphalt and concrete. In road construction, service lives of over 30 years can be achieved. In addition, water, frost, fire, road salt and pollutants, which lead to material fatigue in other asphalts, cannot harm mastic asphalt. The new road surface on the A4 therefore guarantees the client a high level of cost-effectiveness.