Prins Claus Bridge, Dordrecht

Prins Clausbrug, Dordrecht NL, Project Team: René van Zuuk Architekten, Client: Municipality of Dordrecht, Design: 2014-2015, build 2020-2021

Since the new bridge is only 5 meters above water and unlimited vertical clearance is desired for the boats passing by, a unique design principle was chosen: a bascule bridge with a rotating pylon. The pylon extends 30 meters into the air when raised, and is held vertically by a counterweight. Due to the rotating pylon, the opening and the closing of the bridge are turned into a spectacle. A harmonious movement takes place, with the pylon bending over first, and retracting afterwards. At the opening, the pylon moves towards the span, and then comes to a standstill together with the moving part at 85 degrees. When closing, the pylon remains close to the span for the first 45 degrees of motion, after which, it rises majestically.

The supporting structure of the bridge is located in the middle of the deck, an element making it possible to fabricate a slim looking bridge, despite its substantial span. Since the main beam is partly above the deck, a distinct separation between pedestrians and cyclists is created. The height of the beam is 45 centimeters above the deck, allowing it to serve as a seating area. At the location of the span, the pedestrian and cyclist part are separated. Between the two parts of the bridge, the crossing experience is enhanced, as one can have direct visual contact with the water. The technical and operational space of the bridge are located between the main beams and are fully visible once the bridge opens. The rooms are accessed by two staircases, leading the operator under the main beam. Inside the control room, the operator can look across the beams, through a glass skylight.

The streetlights are fixed on the pylon and shielded spotlights brighten the whole deck. The construction itself is illuminated on the northwest side making the bridge visible to the surrounding area. Its anthracite color is in line with the color of the rest of the bridges in the city. The counterweight, the pendulum and the beams differ, with a silver-grey color.

The subtle rotation causes a type of tectonic fracture at the point of the ridge, where the trusses almost meet. The shifted roof surfaces provide indirect daylight through the top. The roof is made out of profiled steel sheeting and cladded with corrugated aluminium on the exterior. Internally, the steel sheeting is partly covered with gypsum plasterboard. Office spaces, restrooms, storage and a little library space, are placed in the main volume, in the form of two autonomous wooden boxes.