The Eiffel Tower is an iron tower built on the Champ de Mars beside the Seine River in Paris. The tower has become a global icon of France and is one of the most recognizable structures in the world.

Named after its designer, engineer Gustave Eiffel, the Eiffel Tower is the tallest building in Paris and one of the most recognized structures in the world. More than 200,000,000 have visited the tower since its construction in 1889,including 6,719,200 in 2006,making it the most visited paid monument in the world.Including the 24 m (79 ft) antenna, the structure is 325 m (1,063 ft) high (since 2000), which is equivalent to about 81 levels in a conventional building.

When the tower was completed in 1889 it was the world’s tallest tower — a title it retained until 1930 when New York City’s Chrysler Building (319 m — 1,047 ft tall) was completed. The tower is now the fifth-tallest structure in France and the tallest structure in Paris, with the second-tallest being the Tour Montparnasse (210 m — 689 ft), although that will soon be surpassed by Tour AXA (225.11 m — 738.36 ft).

Key figures

• Initial height: 312 m (to the top of the flagpole)

• Current height (including antennas): 324 m

• The deepest foundations: (North and West) lie 15 meters

underground. In each of these foundations, four pillars of masonry

are built, which bear the four uprights of each leg of the Tower,

known as rafters.

• Total weight: 10,100 tons

• Weight of the iron structure: 7,300 tons

• Space between the pillars:

1st platform: 4,415 m2

2nd inner platform: 1,430 m2

3rd inner platform: 250 m2

• Height of the platforms:

1st platform: 57 m

2nd inner platform: 115 m

3rd inner platform: 276 m

• Lighting: 336 600-W projector lamps (sodium lamps).

• Number of bulbs for the Sparkling Tower: 20,000

• Number of steps in the East pillar to the top: 1,665

• Number of rivets (total): 2,500,000

• Weight of paint used: 60 tons for each repainting campaign

• Time required for painting: the Eiffel Tower was repainted

in its entirety every seven years.

• Number of elevators: From the ground to the second floor:

5 (one in the East pillar, one in the West pillar, one in the North

pillar, one private elevator in the South pillar for the “Jules Verne”

restaurant and one goods elevator in the South pillar). From the

second floor to the top: two sets of two duolifts.

• Elevator speed: 2 meters/second.

• Passenger flow and capacity of the elevators

North pillar: 920 persons/hour

East pillar: 650 persons/hour

West pillar: 650 persons/hour

Duolifts: 1,140 persons/hour

Jules Verne: 10 persons/ascent

Goods elevator in the South pillar: 30 persons or 4 tons/ascent

• Number of persons working on the Tower:

SNTE: 280

Restaurants: 240

Souvenirs: 50

Other: around 50

• Number of analogical TV stations: 6

• Number of free digital TV stations: 30

• Number of radio stations: 31

• Number of antennas: 120

How to build the Eiffel Tower

source – \wikipedia

A general view of the exterior of the National Aquatic Centre, also known as the Water Cube, lit up at night during the opening of the Good Luck Beijing 2008 Swimming China Open in Beijing, China, 31 January 2008. The National Aquatic Centre, located next to the National Stadium, is one of the main venues for the 2008 Olympics

The Water Cube was initially designed by PTW Architects , CSCEC International Design and Arup with structural Engineers Arup conceiving the structure. The structure was built by CSCEC (China State Construction Engineering Corporation). Comprising a steel space frame, it is the largest ETFE clad structure in the world with over 100,000 m² of ETFE pillows that are only eight one-thousandths of an inch in total thickness, The ETFE cladding allows more light and heat penetration than traditional glass, resulting in a 30% decrease in energy costs.The outer wall is based on the Weaire-Phelan structure, a foam (structure formed by soap bubbles).The pattern is formed by taking a slice through the foam, and it was chosen in preference to the Kelvin foam because the more complex Weaire-Phelan structure results in more irregular, organic patterns than slices through the regular Kelvin foam.The structure will have a capacity of 17,000during the games that will be reduced to 6,000 afterwards. It also has a total land surface of 65,000 square metres and will cover a total of 7.8 acres.