DE
Due to load-bearing capacity deficits, the three bridge structures at the intersection of the A5 and A67 motorways at Darmstädter Kreuz need to be replaced.
As part of the overall project, the structures, the north ramp and the central structure will be demolished and replaced by new structures in steel composite construction. The southern ramp will initially be constructed parallel to the existing motorway, but will also be demolished at a later date.
The north ramp will carry the A67 motorway with two lanes over the A5. The new replacement structure is being built as a single-span, three-span steel composite bridge and consists of accessible steel box girders. The steel structure will be pre-assembled, welded and coated with corrosion protection in the cycle cellar and then slid into place in 3 cycles, with the A5 motorway below being fully closed. The length of the structure will be increased to 170 m to allow for a planned lorry exit lane.
The replacement construction of the central structure will be erected as a 2-part, three-span, wave-shaped trough bridge. Here too, the steel structure is being welded together on site in 2 sections in the cycle cellar, coated and then slid into place bay by bay. The structure now extends over a length of 160 metres.
The south ramp is being constructed as a steel composite structure with 3 conditionally accessible steel box girders. The new structure will be 94 m shorter and will be built next to the existing structure.
The superstructure for all 3 bridge structures should be completed by the end of 2022.
A particular challenge for us was the parallel demolition of the north ramp and the central structure, which was successfully completed within 72 hours. The construction of the three bridge structures was also carried out in parallel in order to minimise disruption to ongoing traffic. The individual shifting cycles of the three steel structures were each postponed at the weekends with short breaks between closures, which were always adhered to on time.
Whether specialised civil engineering, structural engineering, civil engineering and road construction or steel construction - all of these trades are carried out by companies in the Eiffage Group. The efficiency within the Eiffage Group is an important building block for the successful realisation of the project.
