Arup is a engineering firm specialized in building design, infrastructure design, planning and consultancy related services. In our blog we reproduce the recent post published in ArchDaily about the amazing work done in Fulton Center subway station in New York, in which Arup connected the subway station with daylight, approaching this space to the street.
All images belong to MTA-CC/NYCT Arup.
In the early years of the New York City subway system, natural light played a dominant role in the illumination of subterranean spaces. The architecture emphasized a connection to the sky, often through skylights planted in the median of city avenues above — lenses in the concrete sidewalks.
However, it proved extremely difficult to keep the skylights clean, and light eventually stopped passing through. Subway authorities moved toward an almost exclusive reliance on electric lighting. While this allowed for greater flexibility in station design, permitting construction at any location and depth, it also created a sense of disorientation and alienation for some passengers.
For the design of Lower Manhattan’s Fulton Center, Arup, in conjunction with design architect Grimshaw sought to reconnect the century-old subway system with the world above.
Central to this effort is an entry and retail pavilion containing an eight-story dome capped with a glass oculus. The dome’s interior surface is lined with a cable net whose nearly 1,000 anodized aluminum panels redirect sunlight into the subway system below.The cable net and cladding system was based on a concept by James Carpenter Design Associates.
The net itself is a form-found structure, meaning that it assumes a specific shape as a result of the forces applied to and within it. (Fabric roofs are another example of this type of structure.) Stretching between the oculus ring and the two floors below it, the net terminates one and a half stories above street level.
The net is 70ft tall at its peak, with an average diameter of 51ft, for a total area of 8,567ft2.
Our mechanical engineers used computational fluid dynamics (CFD) software to trace how air would flow throughout the space under both normal and emergency (i.e., fire) conditions.The CFD analysis for normal conditions showed that large air exhaust ducts would be required in the atrium due to the space’s size. These ducts (the two bright blue dots near the center of either side of the net) were positioned immediately behind the net, meaning that the cable net segments at this position would need to be able to withstand higher-than-normal air speeds.
Once the design was complete, the construction team provided a mock-up of a small section at the contractor’s Westfield, Massachussetts office in order to confirm the configuration of the net as well as the method of fabrication and assembly. (The general contractor was Plaza Schiavone Joint Venture. Cable net installation was led by Enclos, with fabrication and material provided by Tripyramid Structures).
The Fulton Center will open to the public in summer 2014."
- Arcticle published in ArchDaily.com