Building demolition based on old Japanese game



Kajima Corporation, a Japanese construction company, demolishes high-rise buildings from the bottom up. They install giant hydraulic jacks on the first floor, break up all the building material on that floor, then lower the jacks and repeat the process on the second floor (which is now resting at ground level.)

Informally, this method is called daruma-otoshi, the name of a Japanese game where you remove the lowest block on a stack by knocking it out with a small mallet.

According to Kajima, the daruma-otoshi demolition method – which is now being used to dismantle a 75 meter (246 ft) tall, 20-story building and a 65 meter (213 ft) tall, 17-story building – is safer and creates less noise and dust pollution because the work is kept close to the ground. In addition, this method cuts demolition time by 20% and makes it easier to separate and recycle the building materials.
Daruma-otoshi skyscraper demolition (Pink Tentacle)