CN tower in Toronto, Canada is a communications tower. Prior to Burj Khalifa it held the record for the tallest free-standing structure and the tallest tower in the world. CN stands for Canadian National, the railroad company which built it. Here are a few facts of the CN tower:
Height: 553.6 m
Cost of constriction: $63 million
CN Tower today is a public company owned and managed by Canada Lands Company (CLC), a crown corporation. The tower was built to aid in receiving and transmitting signals for radio communication. Although, rarely used for this purpose now, CN tower has become a popular tourist attraction. Around 1.5 million tourists visit the CN tower annually. The tower boasts of a 360 degree revolving restaurant, an observation deck an edge walk for thrill-seekers and many other such exciting attractions.
This plain simple communications tower held the record for the tallest structure from 1976 to 2010. Indeed it is a marvel of structural engineering.
Burj Khalifa, situated in Dubai is the tallest skyscraper in the world. Here are a few vital stats of of Burj Khalifa:
Height: 828.9 m
Opened : 2010
Cost : $ 1.5 billion
Designed by : Skidmore, Owings & Merrill LLP (Chicago)
Chief architect: Adrian Smith
Burj Khalifa holds the following world records:
Tallest building in the world
Tallest free-standing structure in the world
Highest number of stories in the world
Highest occupied floor in the world
The footprint of Burj Khalifa is three-lobed resembling the Hymenocallis flower. The Y-shaped structure which tapers towards the top provides stability from strong wind forces. The buttressed-core which is hexagonal in shape is made of high strength concrete. The six buttressing wings support the core also provide floor plates at the top. This unique design makes it possible for such a tall tower to stand on its own.
Burj Khalifa was known as Burj Dubai while it was being designed and constructed. However during the financial crisis of 2008, Dubai had to be bailed out by its oil rich neighbor Abu Dhabi. In order to repay the gratitude, Burj Dubai was renamed Burj Khalifa after Khalifa bin Zayed Al Nahyn, the Emir of Abu Dhabi and the President of United Arab Emirates. The emirate of Dubai is using Burj Khalifa to promote tourism in order to diversify its oil-based economy. Burj Khalifa is known for its amazing display of fireworks during New Year celebrations. The tallest man made structure in the world is indeed a structural wonder.