Pile foundation

 PILE FOUNDATION

In case where the shallow foundation has adequate capacity to support the load of the superstructure then shallow foundation is provided but if the soil is poor, the depth of foundation has to be increased in order to safely transmit the load. Because of this increased depth the foundation is known as deep foundation and pile foundation is one such type of deep foundation along with piers and wells.

TYPES OF PILE FOUNDATION

Pile foundations can be classified into different types based on certain criteria. 

1. BASED ON FUNCTION OR USE

A. Sheet piles

B. Load bearing piles 

C. End bearing piles

D. Friction piles 

E. Soil compactor piles

2. BASED ON MATERIAL AND CONSTRUCTION METHOD 

A. Timber piles

B. Concrete piles

C. Steel piles 

D. Composite piles

These can be further classified into the following:

• Timber piles: Untreated and Treated with Preservative 
• Concrete piles: Pre cast piles and Cast in-place piles 
• Steel piles: I - section piles and Hollow piles

But the best way of classifying pile foundation is on the basis of effect of installment of pile on the soil. Based on this pile foundation is divided into 2 types:

• Displacement piles
• Non - displacement piles

USES OF PILE FOUNDATION

• Piles provide load transfer in cases of poor/weak soil.
• In foundations for retaining walls, bridge abutments piles are used to resist horizontal loads.
• Loose sand deposits which get densified by the vibration set up on driving are compacted using piles.
• Piles are useful in resisting uplift loads.