A mile-high skyscraper seems like an impossible dream, but could modern building methods make it a reality? How high can we build?
Sixty years ago a visionary architect, Frank Lloyd Wright unveiled plans to build an ambitious mile-high skyscraper in Chicago. He was way ahead of his time it seems. His design may not have been viable back then, but we are inching ever closer to his goal.
Is it possible?
“The technology and the engineering are there to go as high as we want,” says structural engineer Roma Agrawal. Architect David Malott agrees, “It’s going to look different to what Frank Lloyd Wright proposed, but nonetheless, we understand what it has to be.” So why haven’t we done it yet? The short answer is money. You’d have to have a lot of it! Take for example the Nakheel Tower in Dubai that began construction in 2008. Aimed to be 1, 400m tall, the building’s foundations alone cost a staggering R1,4 billion. Soon after the world economy took a plunge and the project was abandoned. Just as well because the tower was set to cost R540 billion to complete!
Wind-ing up
To build that high there are lots of considerations to be made. Wind being a biggie. “Very slender structures, like Wright proposed, have a tendency to flutter, the same way a flagpole does,” explains Malott. If it does that it can shake itself apart. To prevent this the building needs to be more aerodynamic. You’d need to taper it and round the corners in order to reduce the force that the wind can exert by smoothing its path across the surfaces. Another possibility is to create gaps in the building, allowing wind to flow through it rather than slap against the side.
Materials matter
Though the ‘recipe’ for concrete hasn’t changed since Wright’s days, the method of preparing it and the quality of the ingredients has. “Once we understood the chemistry behind the mix we could play around with it to make the concrete stronger,” Agrawal explains. And there are plenty of advances on the horizon too, which should help solve the biggest problem cement currently has – cracks.
Other issues
- Do we really want to live so high up? People who live in high rise apartments have been shown to feel lonelier and depressed than those living closer to the ground.
- Can a lift even go that high? Lifts can currently only go 500m up. The steel cables required to go any higher would weigh too much to support themselves.
- Evacuation would be an issue. A building over 500m high would take up to 2 hours to evacuate in an emergency. And once you’re over a kilometer high it could take 6 hours.
The world’s current tallest building is the 828m Burj Khalifa in Dubai. This was set to be overtaken in 2020 by Saudi Arabia’s Jeddah Tower, which will be the first building to break the 1km mark, but it is not completed yet.