Elevated Lightrail System, South Korea

The design

The columns supporting the viaduct are Y-shaped. The arms that support  the double track are spread about 30 meters apart, 15 meters above the ground. The steel structure in between the tracks is the backbone of the construction. A capital “I” is the best description of the shape of the combination of deck and structure: at the bottom is the plateau with the tracks, above it is the primary structure of the roof. This results in an always unhindered view of the city for the train passengers sitting on the right side.

To prevent the 200-meter wide span sagging under its own weight ZJA chose to apply a hybrid construction. First there are the supporting arms of the columns, and then the central backbone of steel trusses in a continuous X-shape that add stiffness. Next the roof and its network of outriggers. This openly designed network of steel tubes includes pre-tension steel cables, making sure all the weight adds to optimising the stiffness of the viaduct, while the look of the viaduct retains its lightness and transparency. 

In the architectural design of the roof and the network of outriggers the emphasis lies on organic lines and curves. The roof has an important function in the distribution of forces into the construction and that is why it raises itself in a gentle waive at each column. The viaduct elevating the train is a white and friendly undulating wave gliding through the city. Thanks to the wavy rhythm the appearance of weightlessness is created.

The lighting plan

The roof has a glass covering with optional PV-cells to supply the energy for the lighting of the tracks and viaduct. When developing such an extensive addition to the already dense urban structure the visual impression it makes after sundown is of great importance. For that reason, ZJA developed a sophisticated lighting plan, that first of all lights the tracks for the train driver and the passengers from the centre. It also sees to the lighting of the underside of the tracks and the roof, in such a way that the organic lines and the rhythm in the network of tubes are highlighted. The columns, painted in a light grey colour, in contrast to the white of the steel tubing, have their own lights. The result is a pleasant and soft spacious effect, emphasizing the floating effect of the design.

An asset for the city

Old elevated railway tracks were notorious for their excruciating noise, the shadow and stench and unwanted vibrations they brought. They were bulky obstacles that took away quality of life from the neighbourhood. This contemporary design for South Korea however is an asset for the city. Its design radiates transparency and spaciousness, brings less noise and traffic and more space for trees and pedestrians.

ZJA’s design for the Elevated Lightrail Transit System is a light and lively volume; an open, delicate looking network that undulates gently through the metropolis. Sitting on the train that glides effortlessly and swiftly through the city offers an unhindered view of a bird in flight. An experience that offers quietness and pleasure. Living in a neighbouring building and looking down on the transparent undulating roof and seeing the light play over the trusses and the tubes, one wishes for a moment to be aboard that carriage, weightless among the towers. It is a sight that seems to lift one up, sparking a desire to fly like a bird in a soundless flight, whether one is in one of the towers, on the street or on the platform, with the train approaching.