Work on the temporary bridge over Hildesheimer Straße and Schützenallee on the Südschnellweg in Hanover is being carried out at the tightest possible pace. The swivelling of the light rail line was completed exactly according to plan within a 3-day break in order to construct the bridge foundations in the intersection area. The steel construction for the replacement bridge can therefore begin on time in December.
Since March 2023, the PORR/Stump-Franki/Hagedorn consortium has been renovating Hanover's most important traffic artery at the Hildesheimer Straße / Willmerstraße intersection as part of the planned renewal of the Südschnellweg, which covers a total of around 10 kilometres. Within the first construction phase, the existing bridge will be replaced by a 1,105 metre long road tunnel with upstream ramp structures. Before the dismantling of the existing bridge, a 938 metre long temporary bridge must be built parallel to the elevated road.
Closure break for track work carried out safely
PORR project manager Konstantin Jury is satisfied with the performance so far: "The construction teams have delivered one precision landing after another to date." Around 900 metres of the diaphragm walls north, which also serve as a support for the southern piers of the replacement bridge and as a construction pit boundary for the tunnel, have been installed underground since June. To ensure that work can continue in the junction area and traffic on Hildesheimer Straße does not come to a complete standstill, road traffic and pedestrian paths have been moved around the construction site as a first step. From 3 November at 9 p.m. to 6 November at 3 a.m., there was a break for the track workers. The overhead lines had to be adapted to the new course of the light rail tracks, as public transport will also avoid the construction site in future. After the track was opened, the first tram travelled through the reversal at 03:18.
Special civil engineering, structural engineering, track, road and pipeline construction work hand in hand
In a project of this size, special civil engineering, track, road and pipeline construction, structural engineering as well as steel construction must be tightly coordinated. "Building under rolling wheels requires a high degree of discipline, planning, communication and flexibility," Jury continues. "The construction of such a complex temporary structure in an inner-city location always requires extensive rescheduling, for example due to unknown cables. Despite all this, we have been able to keep to the tight schedule to date." A total of 21 months have been set aside for the planning and construction of the replacement bridge. Construction work on the first abutment has been underway since October, five of a total of 44 bridge piers have already been erected and the diaphragm wall work will be completed by the end of 2023. The pile foundations for the bridge piers on the north side have already been completed. In order to meet the deadlines, special permits have been obtained for work on Sundays, public holidays and at night. Since October, the teams have been working in two shifts from 6 a.m. to 10 p.m. in decade mode. Despite all the time pressure, the ARGE pays meticulous attention to the greatest possible environmental protection. For example, the construction containers are equipped with a grid-connected PV system for a self-sufficient energy supply. The construction site also has its own wastewater treatment plant. This saves CO2, as there is no need for waste disposal journeys.