Types of Deep Foundation in Construction

Deep foundations are foundations whose Df/B ratio is greater than 1. 

The major types of deep foundations used in building construction are:

1. Pile Foundation
2. Mini Pile or Micro Piles
3. Pile Walls
4. Diaphragm Walls
5. Caissons foundations
6. Compensated Foundations
7. Ground Anchors

1. Pile Foundation

Pile foundations are long slender, column-type deep, and, made from steel or concrete or timber. They can either be end-bearing piles or friction piles based on their working mechanism. 

2. Micro Piles

Micro piles are piles that have relatively small diameters in the range of 100 to 250 mm. They can be mini piles, pin piles, needle piles, root piles, and lightweight piles.

3. Pile Walls

Pile walls are piles of concrete, timber or steel units that are placed adjacent to one another to create a permanent or temporary retaining wall. These can be contiguous pile walls, interlocking secant piles, or sheet piles. 

4. Diaphragm Walls

A diaphragm wall diaphragm is a continuous concrete wall constructed in the ground to act as retaining walls to support the underground structure, as a foundation,  or to facilitate cut-off provisions.

5. Caisson Foundation

These are watertight retaining structures that sunk into the ground by removing material from the bottom. 

Image Credits: Offshore Energy

6. Compensated Foundation

These are a type of deep foundation that works on the principle that if the weight of material excavated equals the weight of the building added, the soil is subjected to no additional stress. These are also called floating foundations. 

7. Ground Anchors

Ground anchors are used to transferring very high loads by using a grouted anchor to mechanically transfer the load from a tendon to the underlying ground. The tendon can be pre-tensioned or tensioned by the applied load.

Read More: Ground Anchors