At 828 meters high, Skidmore, Owings & Merrill (SOM)’s Burj Khalifa is the world’s tallest building. The company’s structural engineering teams not only innovated the buttressed core system for the tower’s skeleton, but also produced the Cayan and Pearl River Towers in Dubai and Guangzhou, respectively. These marvels of metal rise sleekly to the skyline while twisting, reshaping themselves, and all but redefining energy requirements for their internal systems.
What typically comes to mind when dreaming up stable skeletons for supertall skyscrapers? SOM consulting partner Bill Baker made the Burj Khalifa stand firm while shaped like—you guessed it—a glass-coated car key coming out of the earth.
The key, if you’ll pardon the metaphor, is the tower’s core. A hexagonal hub upon which the structure is built in segments, this Y-shaped base buttresses three adjoining wings. Built of reinforced concrete and coated in glass, the three wings recede in an upward spiraling pattern, creating an elegant, dynamic shape which reduces wind vortexes. Because air currents are met by a different building shape at each tier, they cannot combine or strengthen into what would be, at these heights, deadly and whiplike gales.
Yet towers this tall take time. Desiring to limit the timeline for the project, Bill Baker and the SOM team aligned the points at which each wing reduces with the building’s already existing framework—that is, they placed structural pillars in line with interior walls on the floors beneath. The result is a smooth ascension through the building from both an architectural and an internal perspective.
Bill Baker’s specialties also include intricate, alternative architectures involving long or complex roof shapes. Perhaps the twenty-year consulting partner found his signature brush stroke, his engineering signature, to be completing the tower’s top by baring its central, thrice-stabilized core as a spire. At that astounding altitude, decor is at a minimum; but after sleekly furnishing the building’s spiral ascent with glass panes, design teams complemented its precise geometry with some ground-level gardens.
SOM’s other projects have admittedly smaller budgets: The Cayan Tower in Dubai and Pearl River Tower in Guangzhou sit at 300+ meters tall—a lofty height, but collectively only about three-quarters of the Burj Khalifa. Yet their efficiency in other areas, such as ventilation, environmentalism, and unique architectural flair, perhaps surpass that of the concrete citadel. The Cayan Tower, for instance, makes a full 90-degree turn as it ascends to the Dubai skyline. Its 75 floors rotate successively from the very foundation. While accomplishing a similar effect to that of the Burj Khalifa’s wind deflection, this helical, dominating element of the Cayan Tower’s design also causes a larger portion of its exterior to face the nearby gulf—an important marketing feature, considering the structure is a residential building. During daylight hours, the tower heats less quickly than the box-shaped buildings nearby, while, once night sets in, a sightseer must hardly twist their neck to see around the glowing city of Dubai, for the tower does so for them.
The Tower is starkly uniform in appearance, yet brilliantly bold in geometrical shape. The ever-alike, rinse-and-repeat nature of the floor levels and interior rooms numbers among the project’s innovative strengths, because of the impressive efficiency in furnishing interiors, selling rooms, and hiding countless balconies which jut, unmarked by the eye, from each. SOM made sure not to misplace structural columns during design, but rather to keep each floor plan uniform to maximize the building’s adherence to the proposed business model. And it worked: The Tower had reportedly already sold eighty percent of its rooms upon completion.
What is there to add? The curtain wall is uniform glass-and-aluminum. The plumbing snakes to the building’s cylindrical core before connecting to other floors—balanced on that same core, or “spindle,” that resists further gravitational twist to the building’s floors, encloses elevator and service shafts, and houses ever-shifting apartment doors. Finally, woven into the twisting framework of the structure is what consulting partner George Efstathiou calls a “kink” for “architectural interest”—two of the walls are offset, so that from some angles the Cayan Tower appears slenderer than in reality, while from others, it dons a shape more reminiscent of an hourglass, its sides flexed like a bow.
Yet SOM outdid themselves again in 2012. The Pearl River Tower in Guangzhou, China, was more environmentally friendly than anything the architectural company had produced before. With a chilled ceiling and ventilation in both floor and walls, the Tower rises in a shape designed to “catch” the wind, deflecting and redirecting air currents to a pair of wind turbines nestled in floors 25 and 50. In sum, the Tower harvests energy almost entirely from natural means. Solar panels increase the sculpted structure’s efficiency levels, further enabling the building’s energy signature to stay low. In fact, SOM’s stated goal was a net zero energy building–a goal they developed before the industry had even determined what “net zero” was. Seeking a building design which generates all the power it uses in one year, the architectural team encountered unanticipated logical and regulatory issues. Practically speaking, energy loss due to power transmission was inevitable; and adherence to project goals notwithstanding, most of the building’s floors are not in use due to change in local policy.
Yet there can be no doubt that, while fairly standard in strategy, the Pearl River Tower combines ecological methodologies in a way never before seen. The project’s main and finishing focus, said managing partner Richard Tomlinson, was not to invent new techniques, but to “put them together in a way that hadn’t been done before.” While questioning standard architectural thinking–even dissecting their own previous assumptions about buildings–the SOM team pushed the limit for sustainability in modern design. Simultaneously among the world’s 200 tallest towers and the few skyscrapers earning the distinguished LEED Platinum certification, the Pearl River Tower stands as a monolith of the future: a landmark that one day will be pointed to as a proof-of-concept for integrated sustainability and green ventilation techniques.
Bill Baker. SOM. (n.d.). Retrieved September 30, 2021, from https://www.som.com/about/leadership/bill_baker.
Burj Khalifa – structural engineering. SOM. (n.d.). Retrieved September 30, 2021, from https://www.som.com/projects/burj_khalifa__structural_engineering.
Cayan tower. SOM. (n.d.). Retrieved September 30, 2021, from https://www.som.com/projects/cayan_tower.
Gonchar, J. (2016, March 9). Pearl River Tower. Architectural Record RSS. Retrieved September 26, 2021, from https://www.architecturalrecord.com/articles/7971-pearl-river-tower.
Pearl River Tower. SOM. (n.d.). Retrieved September 30, 2021, from https://www.som.com/projects/pearl_river_tower.
Shapiro, G. F. (2013, November 19). Cayan tower, designed By Skidmore, Owings & Merrill. Architect. Retrieved September 21, 2021, from https://www.architectmagazine.com/design/buildings/cayan-tower-designed-by-skidmore-owings-merrill_o.
Nick Merrick & Hedrich Blessing