Cities all across the world are dominated by skyscrapers, and engineering advancements have led to designs becoming more ambitious, allowing for the development of breathtaking skyscrapers which serve a functional purpose while being aesthetically pleasing.
One of the biggest advantages with skyscrapers is their ability to maximise space in cities, and throughout history they have also been used to indicate a country’s wealth and plans for the future. In the 20th Century, the two largest skyscrapers in the world were the Sears Tower and Empire State Building in Chicago and New York respectively, but in more recent times the Burj Khalifa in Dubai has become the world’s tallest.
As structures get higher and higher, the question on many people’s lips is how on earth do engineers prevent these colossal constructions from falling over?
One of the first structural questions in the planning stage of building a skyscraper, is what type of ground will the building be developed on? In most cities the ground skyscrapers are built on is far from solid, so engineers are required to become more creative to resolve this issue.
A vital method for anchoring skyscrapers is to use foundations which keep the skyscraper safe and secure. When structures are built on materials such as clay, for example the 95-storey Shard in London, the building’s roots are required to delve deep underground to create a solid foundation. The Shard sits on a concrete block which is held by hundreds of piles, which collectively support the load 53 metres beneath the surface. At this point, the construction reaches a stiff layer of sand, creating a sturdy support which is virtually immovable. To assist with this difficult task, many companies use rigging specialists such as tway lifting, who can fulfil heavy lifting needs in construction with their bespoke service.
Other buildings such as the Empire State Building go 16 metres below the ground, and during the construction of the previously mentioned Burj Khalifa, engineers faced the challenge of extremely corrosive salty water underground. To combat this issue, they used cathodic protection where metal is combined with the concrete base to protect and firmen the steel foundation. This means that the corrosive nature of the salty water will only affect the protective layer, not the weight-bearing steel.
Battling the Elements
Fighting against the wind is an additional obstacle, and this becomes a formidable opponent for skyscrapers. The force of the wind can shift the foundations of a building from up under it, but by creating a strong base which is spread over a wide area, the construction is less likely to move.
Cores can also be used as resistance, creating a stiff backbone from thick concrete walls. Though this would seem sufficient for protection, other measures are often applied to strengthen structures, such as stiff columns and beams which form strong tubes. This allows buildings to follow outlandish designs while remaining safe, and with a combination of cores and tubes, buildings can reach new heights, literally.
There are even examples of buildings using computer systems to maneuver large weights within their building, dependent on the swirling direction of the wind. This reduces the buildings tendency to sway under different forces, and is an advanced method which proves how much engineering has evolved.
We hope you have enjoyed reading this article, and please do comment below with any additional facts to kickstart the discussion!