Eiffel tower - Construction

The Eiffel Tower is constructed of lattice work structure made of wrought   iron. Wrought iron is  a material that can  last  forever if it is painted regularly.  Since it was built for the International Exhibition of Paris in 1889,  it has been painted  every 7 years to prevent it from rust. It took 2 years to complete the structure. It was the world's tallest structure until Crysler building completed in New York, USA in  1930. The tower  weighs 7000 tons and stands 324 metres high including the anttenna. It used about 18,000 pieces of iron held together by  2.5 million rivets.

The Eiffel Tower was one of the first tall structures in the world to contain passenger elevators. Eiffel was one of the first engineers to recognize the importance  of wind forces on tall structures.The open lattice works allows wind to pass through. Thus it  is very airy and resistant to the wind forces. The tower was almost torn down in 1909 after its 20 years  permit expired , but was saved by its use as a telecommunication tower,  and the City  let it stand until today and now become a symbol of France.

Photos- 1995

 Open-lattice wrought iron structure

The  Tower is  also known as Iron Lady or 'La dame de fer'. It was built to  

  celebrate the centennial of the French Revolution in 1889.