The Burj Dubai: Standing Tallest
Officially outgrowing the competition as the tallest building in the world, the Burj Dubai reflects a colossal landmark, representing humankind’s highest architectural achievement yet.
When the Romans built the Colosseum, they used unprecedented engineering techniques that were revolutionary for their time. Parts of the massive structure pose scores of questions about how it was built, after leaving behind nothing but stone and mystery. The same can be said about the ancient Egyptian pyramids and St. Peter’s Basilica in the Vatican. Today, a variety of experts admit they can’t figure out how human beings put together many of the world’s structural masterpieces. It seems history does repeat itself every millennia or so, as humankind builds something extraordinary. And it’s happening again, in Dubai.
Figuring out how the Burj Dubai was built can be left up to whatever distant civilization inherits Earth. As for here and now, we can relish in the remarkable details of what makes up the world’s tallest structure – and it’s a fascinating story. Twice as tall as the Empire State building, the Burj Dubai can be seen by the naked eye from 95 kilometres away. It’s a testament to the tropical city’s ever-expanding infrastructure, which looked like an empty desert just 20 years ago. At over 800 metres or half a mile high, the building employs some of the most advanced engineering techniques known to man.
When Dubai ruler Mohammed bin Rashid Al Maktoum backed the project in 2003, the architectural contract went to Skidmore, Owings and Merill (SOM). Known for famous designs such as the Sears Tower in Chicago and the Jin Mao Building in Shanghai, the company has a reputation for crafting the intricate. “These buildings are like Swiss watches – everything matters,” says Bill Baker, SOM senior partner and structural engineer for the Burj Dubai. His design solved the higher-you-go problem, which suggests that construction is increasingly complicated as skyscrapers become taller.
Baker’s creation of the buttressed core is what allows the Burj Dubai to reach peaking heights. “It’s very good for torsion because it keeps the building from twisting in the wind,” he explains. Three wings shaped like the desert flower Hymenocallis surround the core and make up the base of the building. As the core keeps the wings in place, the tower rises and decreases in mass in an upward-spiralling pattern. It’s something that pleased the building’s developers, who continuously changed the design by asking Baker to make the Burj Dubai taller. Although new heights meant going back to the drawing board each time, Baker didn’t loose confidence. “I could come up with a design for a building that’s a mile high,” he admits. “The only question would be the cost factor and the elevators, which could be a bit of a challenge because of pressure change.”
When it comes to the Burj Dubai’s elevators, there will be no shortage. A total of 56 double-deck cabs carry 42 people at a time. They are among the globe’s fastest, travelling at 40 km/h and programmed for controlled evacuation in emergencies. The spire maintenance elevator, located inside the narrow rod at the top of the building, is the highest in the world. And when you’re up that high, things can get a little
scary – especially for the window washers. Their exterior elevators, or cleaning cradles, are permanently installed machines that are parked in garages on levels 40, 73, and 109. The machines use mechanical arms to literally reach out and wash the building. Of course the job takes some time, requiring six to eight weeks in normal weather.
Another structural work of art is the tower’s curtain wall, costing over $100 million alone. Over 27 acres of glass and metal cover the exterior of the Burj Dubai, equal to the surface area of 25 football fields. After being tested in a Canadian artificial wind tunnel, the windows are proven to withstand winds up to 75 km/h. “We designed the building to resist storms that happen less often than once in a thousand years,” Baker says, whose wind tests changed the Burj Dubai’s form and position. “It led us to reshape the building, and actually turn it 180 degrees. We found that the wind was statistically less likely to come from a certain direction.” And bad weather isn’t the only thing the building can endure. The thin layer of metal covering the windows acts as a form of sunscreen, deflecting solar heat and ultraviolet radiation.
Even more impressive, the Burj Dubai is built with state-of-the-art, high-performance concrete. It’s made up of over five times the amount of concrete used for Toronto’s CN Tower or the equivalent to a sidewalk 1,900 km long. And because of scorching Dubai temperatures, it uses a unique recipe. “You’re worrying about pouring concrete in the middle of the summer because it generates heat when it dries,” Baker explains. “So when we poured the foundation, we added ice to the mix to avoid boiling the water in there.” The building’s geographical location is another reason the Burj Dubai is so safe. “The closer you are to the equator, the slower the wind speeds, as long as you’re not on a coast getting typhoons.”
When the Burj Dubai is completed later this year, its first 37 floors will boast a luxurious Giorgio Armani hotel. Guests who plan on staying a little longer can move into one of the skyscraper’s 700 private condos, although finding vacancy might be a little tough since the million-dollar apartments sold out within eight hours after going on sale. Whether you’re looking to start a business on the remaining commercialized floors or plan a lavish getaway, the Burj Dubai remains humankind’s tallest achievement yet. It’s fair to say even the Romans would be impressed with this architectural crown jewel.
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