The 938-metre-long temporary bridge is the first major step in the renovation of the historic B3 transport axis through Hanover. The PORR/Hagedorn consortium, in which PORR is involved with the civil engineering and foundation engineering divisions, has been working at full speed on the section since 2023. The temporary bridge runs parallel to the existing bridge, which will be replaced in the area of Hildesheimer Strasse and Willmerstrasse by a 1.1-kilometre-long underground subway, including the ramp structures, once it has been dismantled. The temporary bridge will accommodate traffic during the tunnel construction period.
Milestone "Completion of diaphragm wall work" safely reached
The diaphragm wall work for the specialised foundation engineering has now been safely completed. Over a total length of more than 1,100 metres, the diaphragm wall slabs are lined up on the north side of the Südschnellweg. An important milestone for the team and the overall project, which was achieved with flying colours despite the inner-city challenges. Specialised civil engineering is now concentrating on the cofferdams, which serve as access roads for the temporary structure in the east and west. This clears the construction site for the time being and sets the stage for the engineering and steel construction.
In order to minimise the dimensions of the steel components for the temporary structure and speed up the construction time, the temporary structure is made up of 18 individual load-bearing substructures. More than 40 bridge piers have already been built for this purpose. Production of the steel components is running at full speed in parallel in two supply plants. In the Hildesheimer Str. and Schützenallee intersection areas, the first steel components are currently being assembled on site to form the substructures.
Modular production of the steel and concrete parts saves time
With the erection of substructure 13, the project team is facing a new, special challenge with the steel construction in the first quarter. During five consecutive weekend closures in February and March 2024, the team will erect the steel composite bridge at the Willmerstraße and Hildesheimer Straße intersection. Traffic will continue to flow during the construction period, with only light rail traffic having to be suspended at weekends due to dismantled or inactive overhead lines.
Substructure 13 is one of a total of 8 trough bridges. Trough bridges have a lower construction height and are therefore located in the intersection areas of Schützenallee and Hildesheimer Straße, among others. The carriageway is positioned between the main girders and is lower than their upper edge. On the other 10 deck bridges, however, the carriageway lies on the longitudinal girders.
