A pile is basically a long cylinder of a strong material such as concrete that is pushed into the ground to act as a steady support for structures built on top of it. ... When a building has very heavy, concentrated loads, such as in a high rise structure, bridge, or water tank. A deep foundation is a type of foundation that transfers building loads to the earth farther down from the surface than a shallow foundation does to a subsurface layer or a range of depths. Apile or piling is a vertical structural element of a deep foundation, driven or drilled deep into the ground at the building site.