CN Tower

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CN Tower
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CN Tower

• Rock foundation, hollow concrete shaft to 1100',
  7 story steel and concrete "Skypod", 330' of
  hollow concrete shaft supporting the "Space
  Deck", 340' steel antenna mast.
• 1815'-5'' above the foundation,
• tallest freestanding structure.
• 57 million dollars
• three-and-a-half years to build.
• It weighs the equivalent of about 23,200 large
  elephants (130,000 tons), and contains 53,000
  cubic yards of concrete and 5000 tons of
  reinforcing steel.
• Tower was opened to the public in June of 1976.

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Main Tower Features
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Wind Tunnel Testing to Determine Loads
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FoundationBoring Log
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Foundation Considerations
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Foundation Post-Tensioning
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Start of Excavation
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Excavation Near Complete
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Steel and Post-Tensioning Ducts in Place
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Foundation Essentially Complete
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Slip-Forming -- Conceptually
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The Slip-Form
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The Tower Starts
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And rises
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And rises..
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Post-Tensioning Strands
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Location of Strands
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A Post-Tensioning Strand
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Skypod
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Construction of Skypod
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SpaceDeck
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Helicopter used in final phase
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Removing crane
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Placing antennae