THE GOLDEN BRIDGE
Conceived as a landmark for the city of Prague, our proposal for a new pedestrian footbridge in Štvanice Island is a contextual addition to the infrastructural landscape of the Vltava River. By virtue of its timeless form and unprecedented materiality, our proposal will respond to local concerns for an outstanding, elegant and striking structure that will enhance the architectural identity of the city.
Spanning across the two districts of Holešovice and Karlín, our proposal builds upon the site’s rich historical context to create an urban passage that is, at once, timeless in its architectural language, innovative in its structural approach, and experientially memorable. Our design acknowledges that bridges are opportunities for placemaking– and, as such, our goal is to produce a structure that is not only rational, resilient, and efficient; but also architecturally sensible.
Taking formal cues from Prague’s well-established repertoire of historical masonry arch bridges, our proposal is driven by the structural expression of the vault: a tectonic element that takes advantage of basic geometric principles as a means of achieving a highly efficient distribution of forces. Taking this tectonic principle as a starting point, the project’s structural approach is inspired by a type of minimal surface known as “Scherk” surface, which ensures that the transition between perpendicular planes occurs seamlessly and elegantly, while also minimizes the amount of material required for construction. The proposal thus reinvents the archetypal interpretation of the vault in a way that results in a new and unexpected architectural language.
The bridge features a simple and elegant form– one which emphasises the nuances of its geometry and materiality without compromising the historical character of the Vltava River. Inspired by the plasticity and colour palette of Prague’s Baroque architecture, the project consists of three double-curved homeomorphic arched structures that conform to the geometry of a Scherk surface in order to achieve a highly efficient distribution of forces: a 161-metre span along the North bank, a 71-metre span along the South bank, and a smaller 47-metre span sitting atop Štvanice Island. Consisting of an orthotropic steel hollow section, our proposal takes cues from the form, materiality, and tectonic language of the naval vessels that historically navigated the waters of the Vltava River. It is thus conceived as a monocoque steel hull that not only performs efficiently in bending and axial compression, but also draws from local shipbuilding technologies in terms of construction and assembly methods.
Situated in an area of environmental importance, the bridge is designed to high aesthetic standards without disregarding any of the practical requirements elaborated in the brief. In order to maintain navigability on both sides of the crossing, the proposal respects a minimum clearance above mean high water sea level of 9 metres, allowing the circulation of river vessels year-round. Supported by ramped abutments, the bridge will feature a maximum width of circa 10 metres, providing a generous walkway that will satisfy peak-hour traffic whilst still allowing for moments of repose and contemplation.
Located at the junction with Štvanice Island, two fully-accessible ramps will be provided for exclusive pedestrian use, facilitating the flow of traffic into a previously underused green area. These ramps are accommodated within the geometry of the hollow steel section hull, and project through the underside of the bridge to gently descend on the island and subtly integrate with the existing landscape. This approach ensures that pedestrian circulation to Štvanice Island remains fully accessible.
Echoing the metaphor of a ship floating in the waters of the Vltava, the materiality of the bridge is reminiscent of the merchant vessels that once navigated the waterways of Prague. The design proposes cladding the structure with sheets of Muntz metal, an alloy of brass and zinc that has been utilised since 1832 in the construction of ships across Europe. In addition to its ability to withstand long-term damage from corrosion, Muntz metal slowly develops an elegant colouration and patina that will evolve with the passage of time. The result is a remarkable structure that will reflect light differently throughout the course of the day– infusing the site with a renewed sense of identity in a truly unique, simple and elegant way.
Client: The Capital City of Prague
Use: Pedestrian bridge
Structure: Monocoque steel shell
Status: International Design Competition
Architect: LUCA POIAN FORMS
Structural engineer: SOLUXN Ltd