promotion image of download ymail app
Promoted
Anonymous
Anonymous asked in Science & MathematicsEngineering · 1 decade ago

Construction question?

How do they take down those huge cranes up top when those towering skyscrapers are all done?

Also, how do they put them back there when there are some repairs that have to be done?

4 Answers

Relevance
  • KOHA
    Lv 4
    1 decade ago
    Favorite Answer

    The top section has a hydraulic jack that opens a space for a new section. The new section is lifted in (or out) with the jib.

    See illustration @

    http://science.howstuffworks.com/tower-crane5.htm

    Click on option = "How Do They Grow"?

    The process is reversed for the take down.

    _

    • Commenter avatarLogin to reply the answers
  • R T
    Lv 7
    1 decade ago

    There is a device called a Gin Pole. It's a piece of mast that can be attached to the side of the main structure and used as an anchor for a hoist. Once the piece is brought down, the gin pole is repositioned and the process is repeated. This is also how they erect / dismantle broadcast towers.

    Here's an example of one: http://www.k7nv.com/notebook/id7.htm

    • Commenter avatarLogin to reply the answers
  • 1 decade ago

    i still don't know that answer because my professor didn't tell us how it is done. he just told us that we will learn it whe we are in the field. unfortunately, i never had a chance to work in the field of construction.

    Source(s): Mechanical Engineer Registered in the Philippines
    • Commenter avatarLogin to reply the answers
  • 1 decade ago

    Most of them have sytems/methods of self-erection and dismantling.

    • Commenter avatarLogin to reply the answers
Still have questions? Get your answers by asking now.