Type of piles in civil engineering

Piles have been categorized based on the following criteria:
In this article, I discussed various types of piles in detail.
i. Material Used for Construction:
Timber Pile
Steel Pile
Concrete Pile
Sand Pile

ii. Cross Section:

Circular Pile
Square Pile
Hexagonal Pile
I-Section Pile
H-Section Pile

iii. Shape:

Cylindrical Pile
Tapered Pile
Under-reamed Pile

These types of piles are particularly beneficial in expansive soils where shallow spread footings are impractical due to excessive shrinkage or swelling of the soil. A more advanced version of these piles is multi-under reamed piles, where increasing the number of bulbs enhances the pile's load-carrying capacity.

iv. Mode of Load Transfer:

End Bearing Pile: These piles rest on stiff or hard strata, deriving their load-carrying capacity from end bearing action or point resistance. Their length depends on the presence of hard strata.

Friction/Hanging Pile: These piles are driven into soft clay or loose sand, extending to greater depths. Their load-carrying capacity comes from skin friction action. The length of friction piles can range from 10 to 20 meters.

Bearing and Friction Pile: When driven into medium to dense/stiff soil, the load-carrying capacity of these piles results from a combined action of end bearing and skin friction.

v. Method of Forming:

Pre Cast Pile
Pre Stressed Pile
Cast in Situ

vi. On the Basis of Function:

a) Laterally Loaded Piles: Piles can resist horizontal loads, such as in retaining wall foundations and bridge abutments. These are termed laterally loaded piles as the horizontal load acts perpendicular to the pile axis.

b) Batter Piles: For significant lateral loads, piles driven at an angle, known as batter piles, offer better performance than vertical piles.

c) Compaction Piles: Short piles compact loose sand deposits through vibration during driving, resulting in densification.

d) Tension Piles: These piles resist uplift loads and are suitable for swelling soils, such as Black Cotton Soil.

e) Anchor Piles: Piles provide anchorage against horizontal pull, as seen with anchored bulkheads.

f) Sheet Piles: Used to retain earth fills, typically beneath hydraulic structures.

g) Fender Pile: These anchor structures against tidal waves or floating objects in water.

vii. On the Basis of Method of Installation:

a) Driven Piles

b) Bored Piles

c) Vibrated Piles

d) Jetted Piles

a. Driven/Displacement Pile: These piles are driven using hammer action and are often precast from metal or wood. They efficiently develop both end bearing and skin friction resistance.

b. Bored Piles: These piles can be precast or cast in situ and are generally less efficient than driven piles. Based on this, piles can be classified as displacement piles or non-displacement piles. 

Displacement piles displace a significant volume of soil laterally and upwards during installation, densifying the surrounding sand up to about 3.5 times the pile diameter from the center.