Foundations offer structural support and load transmission from the structure to the earth. In contrast, the layer that transfers the load from the foundation to the building must have enough load-bearing capacity and you can opt for a pile footing foundation in this regard.

There are two types of foundations: shallow foundations and deep foundations. Shallow footings are frequently used where the carrying capacity of the surface soil is sufficient to support the loads produced by a structure. Deep foundations are frequently utilized when the surface soil's bearing capability is insufficient to support the loads produced by a building. As a result, the loads must be shifted to a deeper level, where the soil layer's carrying capability is larger.

What is the definition of pile footing?

Pile footing, also known as pile foundation, is a form of deep foundation that consists of a thin column or long cylinder made of concrete or steel. Pile foundations are generally used for big structures and when the soil at a depth is insufficient to withstand excessive settlement, uplift, and so on. If you want to build a structure on land where the water level is high and the soil is unstable to carry heavy loads, you must prepare the ground with the pile footing.

When Should Pile footings be used?

The conditions in which a pile footing system can be beneficial are as follows:

• When there is a lot of water in the ground.
• When there is non-uniform loads and the superstructure is subjected to it.
• Other types of foundations are either too expensive or too difficult to implement.
• When there is a risk of scouring because of its position, such as near a riverbed or the seashore.
• When the structure is located near a canal or a system of deep drainage.
• When it is impossible to excavate to the required depth due to unfavourable soil conditions.
• Pumping or any other method of keeping the foundation trenches dry becomes impractical due to a considerable input of seepage.

Pile Footings Types

Pile footings are classified based on their function, materials, and installation method, among other things. The following are the many types of piling foundations used in construction:

Depending on the Function or Use

Sheet pile Footings

This style of pile is most commonly used to provide lateral support. They are able to endure lateral pressure caused by loose soil and water movement. Cofferdams, trench sheeting, beach protection, and other similar structures are made by such pile foundations. They are not used to give vertical support to the building. They are frequently used for the following purposes:

• Retaining wall construction.
• Protection of river banks from Erosion.
• Keep loose soil out of foundation trenches.
• To isolate the foundation from the soils around it.
• To restrict the soil and thereby boost the earth's bearing capacity.

Load-bearing piles footings

This pile footing foundation's principal function is to transfer vertical loads from the structure to the earth. These foundations transmit loads from a load-bearing layer to a layer with poor supporting characteristics.

Depending on the materials used and the construction method used

Timber or wood pile footings

Timber piles are built beneath the water level. On average, they endure around 30 years. Timber pile footings are available in a range of sizes and forms, including rectangular and circular. They can range in diameter from 12 to 16 inches. Typically, the pile is 20 times the breadth of the top. They are typically designed to support 15 to 20 tonnes of weight.

Concrete pile footings

• Pre-cast Concrete Pile footings

Precast concrete piles are cast horizontally in the pile bed. Typically, circular piles are cast vertically. Precast piles are typically reinforced with steel to reduce breakage during transportation from the casting bed to the foundation position. After the piles are cast, they must be cured in accordance with the manufacturer's instructions. Pre-cast piles generally heal in 21 to 28 days.

• Cast-in-palace Concrete Piles footings

This sort of pile is constructed by drilling a hole in the ground, then pouring newly mixed concrete into the hole and allowing it to cure. This pile type is created by either pushing a metallic shell into the earth or filling it with concrete.

Conclusion

Pile footings are very successful in transferring structural loads into the underlying ground, especially in weaker soils. Current pile design processes are mostly semi-empirical, relying on elastic theories and pile load test data.