I work at an airport and they’re building an 8 level garage and they’re using those big ol’ cranes. Can somebody tell me how they move those things around and how they’re set up? I can see that the main shaft isn’t tapered so that leaves out having it colapse inside itself. My only guess is that they lift up a section, slide another section under it and so on until they have the right height.
The cranes are shipped in pieces and then assembled on-site (another crane lifts a section onto the top and it is bolted on), and then dissasembled when the job is done. There are also self-building cranes that work similar to how you describe, and are able to bolt sections to itself. If that makes any sense.