A pile is a slender structural member made of steel, concrete or timber. In pile foundation, a pile is either driven into the soil and or formed in-situ by excavating a hole and filling it with concrete.
There are piles made of different types of materials used in pile foundation. Generally four types of piles are used in pile foundation depending on materials used for piling.
- Concrete piles,
- Steel Piles,
- Timber Piles and
- Composite piles.
Concrete piles are either precast or in-situ. Cement concrete is used in the construction of concrete piles. Precast concrete piles are prepared in factory or casting yard and cast-in-situ are prepared by making a hole and filling it with concrete.
Steel piles are made of steel pipes usually filled with concrete after being driven. Steel ‘H’ sections are widely used as steel piles, specially if conditions demand hard driving. Steel piles are usually of long lengths and have high working loads per pile.
Timber piles are made of wood. The timber used as timber pile should be straight, sound and free from defects. Steel shoes are provided to prevent damage during driving. To avoid damage to the top of the timber pile, a metal cap or band is provided.
Composite piles are made of two different materials. A composite pile may consist of the lower portion of cast-in-situ concrete. Composite piles are used rarely as it is difficult to provide proper joint between two or more materials.