The Skidmore Owings & Merrill LLP (SOM)-designed Zhengzhou Greenland Plaza has opened its doors to its office users. The circular 60-story tower takes its place as the tallest building in the central Chinese city. Located in the northeast portion of Zhengzhou, the 919-feet tower’s circular form is a response to the surrounding development’s shape that centers on a manmade lake.
The 2.59-million-square-feet building houses a mixed-use program of offices on its lower floors and a 416-room hotel above. Daylighting was a key driver of the building’s design. Three- to five-story-tall light-gauge painted aluminum screens are configured at an outward cant that enhances interior daylighting through scientifically calculated reflections while protecting the all-glass exterior from solar gain. The screens provide multiple performance and aesthetic-related roles. The same outward cant that aids daylighting allows for a nuanced approach to artificial lighting, providing outboard locations for dramatic nighttime lighting of the building that make the tower a beacon. The screens are located between one and two-meters from the building’s curtain wall—allowing window washing to occur behind the screens. Their visual porosity varies depending on a viewer’s location. When close to the building’s base, the tower appears to be primarily metal; from a distance, the panels are more open and the building’s glass nature is revealed. The rhythmic cant of the screens, combined with their decreasing size as they rise on the building, creates a dynamic movement that gives the building a fine-grained texture that relates to the building’s humanistic aspirations.
The form of the tower tapers slightly as it rises. “We conceived the building as a classical column,” SOM Design Director Ross Wimer says. “Its iconic image comes from this timeless form—adapted with cutting-edge, 21st century technologies to create a building that expresses our time.” These innovations include a heliostat that crowns the building and reflects daylight throughout the hotel atrium. “Like the solar screening, the heliostat is a scientifically-derived element that enhances the experience of daylight for the building’s users,” Wimer says. The device allows daylight to be reflected and focused into the atrium whose surfaces are finished to help drive light deep into the space. Computer-controlled dimmer switches modulate the light level-based on the illumination provided by the reflector, enabling the atrium to consume less energy and generate less heat throughout the year.
Wimer notes that, while not unheard of, circular skyscrapers remain somewhat unusual. Among the best known examples are Bertrand Goldberg’s Marina City in Chicago, Sir Norman Foster’s 30 St. Mary Axe in London, Jean Nouvel’s Torre Agbar in Barcelona, and Adolf Loos’ unbuilt scheme for the Chicago Tribune Tower. +
Related Stories
| Jul 20, 2012
Office Report: Fitouts, renovations keep sector moving
BD+C's Giants 300 Top 25 AEC Firms in the Office sector.
| Jul 20, 2012
K-12 Schools Report: ‘A lot of pent-up need,’ with optimism for ’13
The Giants 300 Top 25 AEC Firms in the K-12 Schools Sector.
| Jul 20, 2012
Higher education market holding steady
But Giants 300 University AEC Firms aren’t expecting a flood of new work.
| Jul 20, 2012
3 important trends in hospital design that Healthcare Giants are watching closely
BD+C’s Giants 300 reveals top AEC firms in the healthcare sector.
| Jul 20, 2012
Global boom for hotels; for retail, not so much
The Giants 300 Top 10 Firms in the Hospitality and Retail sectors.
| Jul 20, 2012
Gensler, Stantec, Turner lead ‘green’ firms
The Top 10 AEC Firms in Green Buildings and LEED Accredited Staff.
| Jul 19, 2012
Renovation resurgence cuts across sectors
Giants 300 reconstruction sector firms ‘pumping fresh blood in tired spaces.’
| Jul 19, 2012
Rental market pushing service, ‘community’
The Top 25 Giants 300 AEC firms in the Multifamily Sector keep four-legged tenants in mind.
| Jul 19, 2012
AEC firms ready to dive into public projects
But the size of the pool keeps shrinking for the Top 25 AEC firms in the Government Sector.