STRABAG has won a major contract in Germany to widen the country’s longest highway viaduct to eight lanes. The project is to widen and rehabilitate the Hochstraße Elbmarsch A7 motorway viaduct (K20) in Hamburg.
The work will be carried out by a consortium comprising STRABAG Subdivision Bridge Construction and Subdivision North. The contract was awarded by the German motorway planning and construction company DEGES and the deal is worth over €200 million.
Work on the 3.84km long section is to be completed by 2027.
The elevated Hochstraße Elbmarsch section of the A7 begins a few hundred metres after the exit from the Elbe Tunnel heading south, passes over Rugenberg Port, crosses two railway lines and eleven roads and paths in the Hamburg city limits, and ends at the Hamburg-Hausbruch motorway exit.
STRABAG is currently carrying out the detailed design; at the same time, work has already begun on site installation, demolition and removal, and deep foundation. The aim of the work is to improved traffic flow on central north-south link.
“We are delighted to have been awarded this major German infrastructure project and are gratified by the confidence placed in the capabilities of our infrastructure construction teams. The widening of this busy section of the A7 motorway will improve the traffic flow on Germany’s central north-south link in the long term,” said Thomas Birtel, CEO of STRABAG SE. The daily volume of traffic on this section of the A7 motorway has increased to between 50,000 and 60,000 vehicles in each direction since the construction of the elevated road 45 years ago. STRABAG Subdivision Bridge
The option to widen the viaduct had already been planned for and prepared when the elevated road was built in 1975. The foundations in the port area and the connecting reinforcements on the inner sides of the bridge superstructures, structurally separated for both directions of travel, can now be used for the planned upgrade. The fourth lane will be added to the inner side of each viaduct, bringing the two sections of the A7 closer together. Traffic is to be disrupted as little as possible during the construction work. The widening will be carried out in steps to allow traffic to continue to flow along three lanes in both directions at all times.
The upgrade will begin on the carriageway in the direction of Flensburg (north), with work scheduled for completion by mid-2024. This will be followed by the start of the second phase, the widening to four lanes of the carriageway in the direction of Hanover (south). Three further STRABAG Group entities are also involved in this project: STRABAG Business Unit Hamburg (road construction), Züblin Stahlbau GmbH (steel girders) and Zentrale Technik Hamburg (planning).
The widening of the Hochstraße Elbmarsch elevated road will involve the use of around 19,200m³ of concrete. In addition, 15km of steel railing will have to be renewed. The rehabilitation of the roadway will require the removal of asphalt and waterproofing over an area of 135,000m² and the laying of new asphalt over an area of 155,000m².