The Amazing Tricks Used to Build Skyscrapers
How do cranes get on top of buildings?
This has always been something that left me baffled. There are actually three main methods that can be used to make it happen. The internal climbing method, the skycrane method – where helicopters airlift it the crane into place, and the External Climbing Method. In this method, the base of the crane is connected to the ground in a big concrete slab. Once the building has reached 15 stories high, they start to attach the crane to the building with steel collars. As the building grows they attach new sections to the crane to make it higher. To do this, cranes have a climbing section that temporarily supports the top (the arm) while a new section is fixed into place. Job done.
Earthquake Proofing Skyscrapers
Engineers have advanced so far in their building techniques that they believe it’s possible to construct earthquake-proof buildings. The problem is that it would break the bank to build them that way, so earthquake-resistant buildings are the compromise. The aim of this design is to prevent total collapse. Modern skyscrapers use bearings, giant springs and cylinders at the base of the building to absorb the shock from a big quake, just like your car’s shock absorbers. This allows buildings to ride the wave of the quake and when a big one hits, they can sway several feet in either direction. Another technique is to use dampers to reduce the sway. These are used for quakes and high wind protection.