Laying the groundwork for a strong transport link.
Just a few kilometres south of the seaport of Gdansk, the first 90 km long section of Poland’s A1 motorway was built on what is Europe’s largest construction site. Some 3,000 people were employed on the first section of a north-south route through Poland. When completed, the A1 will have a total length of 582 km and will connect the Baltic seaport of Gdansk with Vienna and Southern Europe, passing through the Czech town of Brno and through Bratislava, the capital city of Slovakia.
As the north-south link through the heart of Europe will have to withstand a high percentage of heavy traffic, the pavement was designed to fully meet these requirements. The existing soil was stabilized at a depth of 50 cm first and then overlaid with a 20 cm thick frost blanket, followed by a 4-layer asphalt package with a total thickness of approx. 26 cm. One of the biggest challenges to be mastered was the highly inhomogeneous nature of the existing soil on the 90 km long motorway section.
Ten stabilizers WR 2000 and WR 2500 S from Wirtgen, and some 30 single-drum compactors and pneumatic tyred rollers from Hamm were working simultaneously on different motorway sections to produce a stable subgrade with good bearing capacity. Single-drum compactors type 3412 HT P with padfoot drum were used in some sections, but most of the compaction work was carried out by single-drum compactors type 3412 HT VIO fitted with smooth drums. These machines can work with either oscillation or vibration, depending on the soil to be compacted. The subgrade was given a perfect surface finish by pneumatic tyred rollers type GRW 10 and GRW 15.
Depending on the properties of the soil, the subgrade material was stabilized in either one or two machine passes. In some instances, both layers were processed with different mixtures of lime or cement to produce homogeneous construction material.
The engineer responsible for the procurement and operation of the entire fleet of construction machinery was delighted with the performance and productivity of the Wirtgen stabilizers, “We have chosen only the very best machines for this highly demanding project.” Given the two big challenges posed by the project – its huge dimensions and extremely tight time schedule – he made the right choice when deciding to use the powerful machines from the Wirtgen Group.
|Job site:||A1 motorway, Poland|
|Project length:||90 km|
|Paving width:||4 lanes of 3.75 m width each|
|Total width:||28.5 m (including grass verge)|
|Working depth:||50 cm|
|Binding agents used:||lime, cement|