Pusan Highspeed Railway Complex
Client: Busan Metropolitan Government
Team: Alejandro Zaera-Polo, Farshid Moussavi, Kenichi Matsuzawa, Lluis Ortega
Associate Architect: Young Joon Kim
Travel is no longer an event, but an everyday routine. Our proposal for a new high-speed railway for the City of Busan aims at incorporating the transportation infrastructure into the urban structure of Busan.
The eastern waterfront of Busan used to be the location of the industrial harbour, and the entire infrastructure associated with it. The railway lines and the main traffic artery of Chungjang Road have severed the links between Busan and that waterfront. Our proposal for the Highspeed Railway Complex is to turn the roof of the terminal into a waterfront deck, that, placed at level +15.70m, will give the citizens the possibility of regaining visual control over the bay area, and to produce a public space where the civic life is strongly related to the waterfront.
The scale of construction and the public nature of the complex provide an ideal opportunity to bridge the urban ground over the tracks and over Chungjang Road, and to connect the urban centre with the seashore.
The station has to provide service to both the highspeed link and to the local rail lines, integrated into a single structure. The volume of the passengers and the frequency of the trains in the station, —one highspeed train to Seoul every four minutes— encouraged us to see the station as a terminal for a ‘national subway’, having Pusan, Seoul and Daejeon as sectors of the same metropolitan structure. The need for a more efficient traffic system to handle this amount of passenger flow suggested an airport-like system, with differentiated arrivals and departures.
Our proposal for the Concourse is to provide a very large, structure-free space, interweaved with the ‘Ocean-Plaza’ in order to create a smooth connection to the outside. On each side of the Concourse, four ‘bays’ will provide access to the four groups of specialised platforms, Arrivals and Departures, for both regular and highspeed trains.
From the concourse to its western side passengers will be able to reach Pusan Subway Station, the Metropolitan Bus bays, a short-term car park, and a taxi drop-off/ pick-up area.
The concourse spans the rail tracks at level +8.50m, the lowest possible level given the required headroom for the trains, and bifurcates either towards the docks/ waiting rooms to access the platforms, or to the plaza-level/ drop-off zone at +15.70m. By locating platform access control in the docks, the aim is to turn the concourse into a conditioned urban bridge over the tracks, suitable for the entertainment and commercial activities that serve not only the station complex, but also the city as a whole.
As the existing station should remain operative throughout construction, the structural system is governed by the platform lines. A system of arches running parallel to the platforms supports undulating decks in the form of a shredded surface, striated in the direction of the tracks. The arches allow the introduction of a large-span structure that reduces the interference of the structural system with the tracks and maximises the visual presence of the structure of the building.
In order to provide the openings in the surface that will allow ventilation and light to enter the station area, the roof deck is supported on eye-shaped Belfast-trusses with 4.0m structural depth, spanning the crowns of the consecutive arches. The deck will alternate between being supported by the lower member of the truss and the upper one., behaving sometimes more like a low arch, and sometimes like a catenary.