Suspending Disbelief

Skidmore, Owings & Merrill accomplishes the incredible at China Poly's colossal Beijing headquarters

C.C. Sullivan -- Interior Design, 7/1/2008 12:00:00 AM

How do you hang one building inside another? More important, why try? Faced with a prominent client and a prominent corner plot on Beijing's Second Ring Road, Skidmore, Owings & Merrill found a reason—and a way. The result astounds, yet the rationale for suspending a large chunk of China Poly Group Corporation's 1 million-square-foot headquarters inside the other was not architectural theatrics but rather a question of functional needs. The energy, defense, and real-estate conglomerate was looking for a powerful civic presence and a mix of uses, starting with shops and a subway entrance. Known locally for a concert hall and a collection of Chinese antiquities, the company also hoped to include a public museum.

With echoes of Kevin Roche John Dinkeloo and Associates's Ford Foundation headquarters in New York, SOM's scheme evolved around a glass-enclosed atrium. It's embraced by an L-shape office block, each leg of which turns its back on Beijing's hot sun with the help of a travertine screen. To keep the atrium as public as possible, it's fronted by one of the world's largest cable-net glass curtain walls.

And the volume suspended inside? Well, something had to hold up that huge curtain wall, and bulky trusses seemed inelegant, SOM's structures-savvy design partner Brian Lee says. That's where the shops, restaurants, and fantastic collection of Buddhas and zodiac figures came in: They'd be housed in a glass box that would serve as a counterweight. "We conceived it as a glowing lantern in the atrium, " Lee says. "People actually pass underneath." His lantern hangs from two V-shape sets of cables, tied together with colossal rocker mechanisms. Both double as rigging to secure the curtain wall. To get the heroic engineering right, SOM employed everything from elasto-plastic analysis software to basswood mock-ups; in the latter, drafting-table wire stood in for the cables.

The impressive result offers seismic benefits, too. "In an earthquake, the lantern stays fixed because the cables maintain tension, preventing failure," Lee explains. Good thing.

From top: Travertine surfaces the lobby's floor and lower walls. Stainless steel suspension cables, 1 foot thick, not only support the lantern but also serve as bracing for the atrium's cable-net curtain wall. Fluorescent lights illuminate the 24-story facade.

FROM FRONT KME GROUP: CUSTOM BRONZE PANELS (ATRIUM). KABELWERKE BRUGG: CABLES. SHANGHAI YAOHUA PILKINGTON GLASS CO.: CURTAIN WALL GLASS. THROUGHOUT CHINA SOUTHERN GLASS TECHNOLOGY HOLDING CO.: GLASS. KANGLI STONE GROUP: STONE SUPPLIER. BEIJING SPECIAL ENGINEERING DESIGN AND RESEARCH INSTITUTE: ARCHITECT OF RECORD. FLACK + KURTZ: MEP. BEIJING TSINGHUA GONGMEI: MILLWORK. ENCLOS CORP.; YUANDA ENTERPRISE GROUP: CURTAIN WALL CONTRACTORS. CHINA STATE CONSTRUCTION ENGINEERING: GENERAL CONTRACTOR.