Motorway interchange Mainz-South is an important traffic hub, connecting the highly frequented routes from Rhineland-Palatinate to Frankfurt and to the Rhine-Main region. At the interchange, motorway A60 passes over A63 and both motorways are connected by ramps. A standard inspection revealed that the structures from the 1960s require rehabilitation and need to be replaced by new structures.
Construction at the interchange started in the summer of 2017 with the south bridge. SSF Ingenieure is only involved in construction of the second phase: design of the north bridge. Dismantling and renewal of the north bridge were advertised together in a functional tender. SSF, contracted by Max Bögl construction company, is responsible for project planning and structural engineering.
The north bridge was dismantled last summer – subsequently, new construction started. The new structure on deep foundations, is a VFT® (composite prefabricated girder) bridge, with six girders running over three spans.
In September, foundation works began – in total 56 bored piles with a length of up to 21 metres were built. After completion of the bored piles, construction of the abutments and both pile axes started. Three round supports were concreted per pile axis, on one of which the bridge’s longitudinal retention is located.
Last week, during a road closure, the girders were assembled. 18 steel girders with concrete complements were placed by a crane, and by two cranes at the central span. The challenge was to manoeuvre the around 30-metre-long and 50-tonne-heavy girders millimetre by millimetre into their place.
The successful assembly of the girders is an important milestone. Now, the deck slab will be concreted. Traffic is planned to roll over the new bridge by the end of this year.
