Every building has it`s fundament, a "something" which the building puts it weight on. This "something" is for a skyscraper an underground substructure. The structure is built up from under the ground. When the whole skyscraper is up the substructure built under the ground takes off much off the weight, and is capable to do so since it is built under the earth. It is able to spread the weight around it`s area, which gives the skyscraper it`s firm and solid stand on a large and solid area and material. How the skyscrapers are build from here, take a look at skyscrapers and vertical columns.

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