Tall trees in the forest sway in the wind. So do tall skyscrapers in the city but you just don’t notice it as much. So how do these very tall buildings stay up?
The walls of a skyscraper are made of stone, concrete, glass, or metal. Under the walls is a frame of concrete or steel. This frame is strong enough to hold up the walls and floors. But it can also bend very slightly in the wind-like trees do. A tall tree has deep roots that hold the trunk and branches. Tall buildings have deep foundations. The foundation holds the steel girders in the ground.
The builders dig down until they find solid rock to build. The builders dig down until they find solid rock to build the foundation on. If there is no rock and the ground is soft, the basement is built on piles. Piles are deep holes bored into the ground. The holes are filled with steel and concrete. This gives the building a sturdy base to rest upon.
Picture Credit : Google