Pile foundations are the part of a structure used to carry and transfer the load of the structure to the bearing ground located at some depth below ground surface. There are many reasons a geotechnical engineer would recommend a pile foundation over a shallow foundation, but some of the common reasons
are very large design loads, a poor soil at shallow depth, or site constraints(like property line
s). There are different terms used to describe different types of deep foundations including deep, drilled shafts, caissons and piers. Pile foundations can be made out of timber,steel, reinforced concrete and pre-tensioned concrete. Pile foundations can be installed by either driving them into the ground or drilling a shaft and filling it with concrete, mass or reinforced. Foundations relying on driven piles often have groups of piles connected by a pile cap (a largeconcrete block into which the heads of the piles are embedded) to distribute loads which arelarger than one pile can bear. Pile caps and isolated piles are typically connected with gradebeams to tie the foundation elements together; lighter structural elements bear on the gradebeams while heavier elements bear directly on the pile cap.
