Why pile caps are required in multi-storeyed building?

Why pile caps are required in a multi-storeyed building?

            A pile cap is a thick concrete mat, rest on concrete or timber piles. Pile has driven into the soft or unstable ground to provide a suitable stable foundation. It usually forms a part of the foundation of a building, typically a multi-story building, structure or support base for heavy equipment. The cast concrete pile cap distributes the load of the building into the piles and resists shear due to gravity. It is constructed above the pile foundation.

            

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