Burj Khalifa structural engineer Bill Baker on the groundbreaking systems that safeguard the building

When the Burj Khalifa officially opened its doors to the world on January 4, 2010, it wasn’t just the tallest structure on the planet — it was a bold declaration of human ambition. For Dubai, this record-breaking building served as the crown jewel in its extraordinary transformation, from a desert port to a thriving global metropolis in less than two decades.

From its breathtaking views at the top to the lives it houses within its residences, offices, and hotels, the Burj Khalifa has seamlessly integrated into the fabric of Dubai’s everyday life, becoming a defining cornerstone of the nation’s identity. As the iconic skyscraper celebrates its 15th anniversary on January 4, this feat remains a career-defining milestone for countless people, including Bill Baker, the structural mastermind behind the building.

“We were pushing the boundaries of what was structurally possible. The idea was never to just create the tallest building in the world but to ensure it was efficient, sustainable, and adaptable to the environment,” recalls Baker, the principal structural engineer on the project.

Baker’s own journey into the realm of engineering seemed almost predestined. Growing up in a small American town, he discovered his calling after taking a high school aptitude test. “I went home and asked my mother, ‘What’s an engineer?’” Coincidentally, both of his late grandfathers had been structural engineers. “Maybe it’s genetic,” he chuckles.

After a brief stint with an oil company, he found his true passion in structural engineering, a journey that led him to Skidmore, Owings & Merrill (SOM), a firm renowned for its work on iconic tall buildings like the John Hancock Centre, Willis Tower (formerly Sears Tower) and the Burj Khalifa.

By the time Baker joined SOM, the firm had already set a legacy in skyscraper design, holding the record for the world’s tallest building for decades. “I worked with people who had worked on those tall towers. Eventually, I became a partner and continued that tradition,” he adds.

The Burj Khalifa’s story began in 2003 when Emaar Properties, led by Mohamed Alabbar, approached SOM with an audacious vision: to create the tallest building in the world. Reflecting on his initial reaction, Baker says, “I already had several ideas on how to do the world’s tallest buildings. So, when they approached us, I thought, ‘Yes, we can do this.’”

Initially designed to be 518 metres tall, the project underwent significant refinements, eventually reaching a height of 828 metres. “The height increase wasn’t planned at the outset,” he explains. “As we refined the design for wind dynamics, we realised we could go taller while reducing wind forces and costs.”

Taming the wind: A critical challenge

One of the most fascinating challenges Baker faced was managing the wind’s impact on the structure. “In tall buildings, wind behaviour is critical,” he adds. “When wind passes an object, it creates vortices that can cause the building to sway.” Through rigorous wind tunnel tests and reshaping the tower’s design, the team minimised these effects.

“We added setbacks and varied the building’s shape. Imagine if the original design worked at 518 metres — we might have stopped there. But the need for refinement allowed us to grow by 310 metres, a height equivalent to the Eiffel Tower,” says Baker.

This meticulous attention to wind dynamics ensured the Burj Khalifa is a “very quiet building” compared to others of its size. “It moves much less than many buildings that are half as tall,” Baker remarks with pride.

A new structural system

At the heart of the Burj Khalifa’s engineering success was also its innovative structural system: the buttressed core. “The core is an irregular hexagon, torsionally stiff like an axle. But to go taller, it needed to be buttressed,” Baker explains. The three wings of the Y-shaped tower act as stabilisers, resisting wind forces collaboratively. “It’s like a Gothic cathedral, where buttresses provide structural support.”

This groundbreaking system, developed specifically for the Burj Khalifa, has since influenced other tall building designs. “It was the first time something like this was done, and it worked remarkably well,” Baker says. “It’s hard to make something simple, but simplicity is where the success lies.”

The Y-shaped design, with three wings and six sides, also minimises sun exposure, enhancing energy efficiency. “Only one-sixth of the building is in the sun at any given time, making it an incredibly energy-efficient skin,” he added.

Roots in sustainability

Decades before sustainability became mainstream, the Burj Khalifa was designed with features like fresh water harvesting from air conditioning systems and leveraging its microclimate at higher altitudes. “The tower’s design harvests the equivalent of 20 Olympic-sized swimming pools of fresh water annually,” Baker added. “Even at 160 stories high, it’s pleasant — it’s a different climate with less dust and clearer air.”

The structure of Burj Khalifa rests on a mat supported by 194 concrete piles, each 45 metres deep. Despite its colossal weight, the building settled by just 50 millimetres — the width of two thumbs. “That’s tiny for a building of this size,” Baker points out. “It’s a result of precise engineering and understanding the soil’s nature.”

Dubai’s sandy landscape posed its own challenges, but beneath the sand lay calci-siltite, a type of soft rock. “It’s naturally cemented together, providing a stable base. We designed the foundations to distribute the load across a large area, ensuring minimal settlement.”

A feat of collaboration

For Baker, the Burj Khalifa’s success was a result of seamless collaboration between Emaar, SOM, and a global team of contractors and consultants. “Everyone knew this was world-class, and they brought their A-game,” he says. “The contractors — Samsung, BESIX, and Arabtec — worked like a symphony, with each partner excelling in their role.”

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