A pile cap by definition is a thick concrete mat that rests on concrete or timber piles which have been driven into 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.  Pile foundation is required when the soil bearing capacity is not sufficient for the structure to withstand. This is due to the soil condition or the order of bottom layers, type of loads on foundations, conditions at site and operational conditions.  It consists of two components: Pile cap and single/group of piles. Piles transfers the loads from structures to the hard strata, rocks or soil with high bearing capacity. These are long and slender members whose length can be more than 15 m.

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