From the architect. Two slender ramps, two half-ellipse shaped steel-arcs and a series of steel-ties lifting up the floating road-track is all: the new fly-over at the Völklinger street in Düsseldorf, Germany, does not need anything further to smoothly move traffic into the harbour. Two symmetrically set steel arches appear to effortlessly grapple with the traffic load: With a light touch and graceful gesture they greet all visitors coming into the city from the south. In front of the skyline of the city-gates and the Rhine-tower they create another architectonic highlight; a delicate horizontal sweep gives a harmonic contrast to the peaks of the Düsseldorf silhouette. Road infrastructure once called the millipede in the centre of town amidst the “Schauspielhaus” and the “Dreischeibenhaus” now has a counterpoint with the “Überflieger” in the centres periphery.
The architecture office Ağırbaş / Wienstroer from Neuss, Germany designed a bridge that appears almost weightless and gets away requiring only few supports. It's not an aesthetic game but is purely functional: Fewer pillars result in a crossing with minimal visual obstructions deliberately enhancing traffic safety. The primary weight of the structure with its 4m wide road and 2m wide verge is carried by the two steel arches. A mayor waste water collecting canal underneath the Völklinger street posed specific constraints for the foundation of the bridge structure. Approaches other than deep pile foundations were discarded from the outset. These pile foundations – safely anchoring the bridge in the ground of the Rhine river valley – carry the weight of its daily users. The “Überflieger” creates new routes across one of the most used road-crossings in Düsseldorf: directly leading into one of the most dynamic locations of the North Rhine-Westphalia capital.
The harbour of Düsseldorf is a special success story. The partial redevelopment into a media-harbour and the further expansion of the pre-existing industrial harbour required this new road-infrastructure like life needs water: The new fly-over connection across the Völklinger street into the developments of Plock street is indispensable. The bridge provides enhanced capacity to smoothly connect the increasing traffic loads into the harbour for both commuter and commercial traffic. Alongside it secures a persistent flow of all traffic moving away from the city centre extending out of the mayor road-tunnels flanking the Rhine. All commuters have to be thankful for the existence of the “Überflieger”.
The architectural contextualisation of the bridge construction succeeds in its playful manner: a gentle rising slope with a slight, calm left turn that – without stopping – dips back down just as gently. A short ride on the “Überflieger” replaces long cues with long waits on a critical left turn. No matter whether small car or lorry, the entire traffic towards the harbour is routed over the bridge ramps into Plock street. Right-turn traffic coming from the town-centre side seamlessly joins at ground-level. To create minimum visual impact on the flowing traffic the entire bridge structure was kept as short and narrow as possible. As a result the ramps made out of reinforced concrete have a continuous rise of six percent whilst the road slants inward at 2.5% within the curve section, altogether a finely balanced geometry resulting in a high driving comfort and design aesthetic. The slender steel arches leave plenty of sight-lines onto the road-traffic.
An atmospheric, colourful illumination at night delivers an aesthetically pleasing architectural experience of the traffic. Technically the bridge has been realised through a composite steel superstructure made out of a seven cell, hermetically sealed and welded hollow core with a composite concrete top slab. Together these provide a low inspection and maintenance overhead. Aesthetically as well as technically and economically the “Überflieger” proves to be a truly innovative design that sets a new momentum for the South of Düsseldorf.