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LD+A The Magazine of the Illuminating Engineering Society of North America

Lamps & Fixtures in the Field  


Channel Surfer

A stunning new bridge spanning the Maqta Channel in Abu Dhabi rides a smooth wave of color-changing light

BY PAUL TARRICONE

 

C all Abu Dhabi, UAE, the land of the bold gesture. Why simply build a hotel when you can build a hotel with a Formula 1 racetrack encapsulated by an illuminated steel and glass shell, as was the case at the Yas Marina? When a mammoth new mosque rises, the lighting design, alone, requires six years, the construction lasts 15 years and the finished product becomes a national icon.

Another bold gesture follows in 2011: After eight years of construction, a striking new bridge—with colored light that flows across its arches—creates a new eight-lane gateway from the Dubai mainland to the island of Abu Dhabi.


The hallmark of the 842-meter (2,762-ft) long Sheikh Zayed Bridge are the three curved steel arches of differing heights that spring from concrete piers. The arches’ undulating shape has been likened to that of a desert sand dune. The main arch soars to a height of 60 meters above water level, with the road crowning to a height of 20 meters above mean water level. In an unusual architectural twist, the bridge’s wave-like structural form—or “spine”—splits and diverges under the deck to the outside of the roadway at one end of the bridge.

The lighting strategy, developed by HollandsLicht and Arup, relies on subtle color-changing light that flows smoothly across the bridge’s silhouetted spine both over and under the deck. This system is complemented by linear fluorescent luminaires tucked into “light cells” embedded under the bridge deck, which provide white light.

FLUID SITUATION
The design scheme is steeped heavily in symbolism: “It is a metaphor for energy flowing across the water [the Maqta Channel], visualized by colors of light cross-fading from one to another while simultaneously moving along the bridge’s spine,” says HollandsLicht lead designer Rogier van der Heide (now chief design officer and vice president at Philips), who was contacted by world-renowned architect ZahaHadid in 2000. As the sun sets, the bridge structure appears to dematerialize due to this fluid movement of light. At night, the lighting renders the spine three-dimensionally by projecting different colors on horizontal and vertical surfaces.


For its part, the roadway lighting (Philips Lighting) consists of asymmetric metal halide luminaires that offer precise beam control so as not to interfere with the thematic lighting. By integrating the roadway and theme lighting, van der Heide ensured that they didn’t disturb each other and instead strengthened the overall concept. With that goal in mind, van der Heide, in collaboration with Hadid, designed the masts that support both the roadway lighting and architectural lighting positioned along the deck.

More than 300 metal halide luminaires (two different fixtures from Martin Professional) provide the colored illumination. Along with the pole-mounted fixtures at deck level are luminaires that sit under the bridge, at water level, and uplight the steel spine as it curves under and over the deck. Dust-proof and waterproof equipment was essential, says van der Heide, and both metal halide luminaires used have an IP65 rating.

TELLING THE TALE
To bare Abu Dhabi’s “soul” through light, Arup’s Simone Collon programmed 13 artistic lighting scenarios, which celebrate Abu Dhabi’s religious traditions, festivals and other public events. In addition, when there is a new moon, the bridge lighting complements the lighting of the nearby Grand Mosque, whose façade illumination is based on the lunar cycle and seven color shifts. Once a month, both architectural landmarks are tinted in deep blue. The lighting scenarios “go far beyond simple color changes,” says Collon. “They tell the story of a very special culture and city.”

Also helping to tell the Abu Dhabi story are flashes of white light that emerge from rectangular light cells beneath the bridge deck. This kinetic light is generated by 956 linear fluorescent luminaires (Martin Professional) fitted inside these light cell compartments. “The cell lighting is carefully integrated into the artistic concept of the color flows,” says Collon. “Sometimes the light pulsates, travels fast from one shore to the other or shows random patterns.”

The vibrant bridge is not only an architectural touchstone and physical gateway to the city but is also being trumpeted as a potential catalyst for economic growth in Abu Dhabi. Fortune may literally follow the bold.

Photos: Christian Richters

September 2011

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