Eiffel Tower

View from the base of the Eiffel

Built in 1887 to 1889 as the entrance of the World Exposition, the Eiffel Tower has become the icon of France. Visited by a staggering 200 million people since it was built, each year sees an average of over 6 million visitors alone. Imagine the amount of tourism revenue generated,hotel rooms booked, croissants, baguettes,air fares,train rides,and lots and lots of wine drunk just due to Eiffel alone. The Eiffel Tower is an engineering marvel which was once the tallest structure in the world. Its height at the roof is 300 m (986 ft) and at the antennae top it is 324 m or 1063 feet. It was intended after the Expo to be used as a communications tower and after 1920, it was returned to the city of Paris.

From 1889 to 1930, it was the world's tallest building until the Chrysler Building in New York beat it when it was built, reaching a height of 319 m or 1047 feet.


View from the Champs de Mars

Designed and built by the engineer Gustave Eiffel, and his team, it took 300 workers almost 3 years to finish. Using puddled iron, it weighs 7300 tons of iron and its total weight including the non metallic base structure and foundation is only 10000 tons - very lightwieght. He was very careful in his design taking into consideration wind resistance and wind shear. On a hot day, it expands by 18 cm away from the heat of the Sun. Also, it sways about 6 - 7 cm daily due to wind force.


Underneath the Eiffel Tower

Gustave Eiffel's creation was met with alot of criticism with many calling it an 'eyesore'. However, his brilliance as a designer and an engineer saw his product stand the test of time and is today the one of the most recognisable structures in the world. He used a non-linear differential equation when designing the structure based on counter - balancing the wind pressure with the tension between the construction elements at the point. A most recent engineering study showed that in fact, there were 2 non-linear equations being applied to the tower, one for the base till the lower structure and one for the upper structure.

Sheer brilliance.