- Project plans
- Project activities
- Legislation and standards
- Industry context
- Specialist wikis
Last edited 23 Sep 2020
Foundations provide support for structures, transferring their load to layers of soil or rock that have sufficient bearing capacity and suitable settlement characteristics to support them. Very broadly, foundations can be categorised as shallow foundations or deep foundations.
Pile foundations are a type of deep foundation, formed by long, slender, columnar elements typically made from steel or reinforced concrete, or sometimes timber. A foundation is described as 'piled' when its depth is more than three times its breadth.
Pile foundations are principally used to transfer the loads from superstructures, through weak, compressible strata or water onto stronger, more compact, less compressible and stiffer soil or rock at depth. They are typically used for large structures, and in situations where soil may be subject to excessive settlement.
End-bearing piles develop most of their load-bearing capacity at the toe of the pile, bearing on a hard layer of rock or very dense soil and gravel. The pile transmits the load through soft, compressible strata directly onto firm strata. This type of pile therefore acts in the same way as a column.
This is as opposed to friction piles (or floating piles) which develop most of their load-bearing capacity by shear stresses along the sides of the pile, and are suitable where harder layers are too deep to reach economically. The pile transmits the load to the surrounding soil by adhesion or friction between the surface of the pile and the soil. In this case, the whole surface of the pile works to transfer load to the soil.
 Find out more
 Related articles on Designing Buildings Wiki
Featured articles and news
Training reflects updated guidance in BSRIA BG 29/2021.
Complete list of 2021 winners now available.
Recognising past and present role models for the future.
So why not write something?
LETI publishes guidance for energy efficient home retrofits.
Predictions about adequate post-pandemic IAQ in non-domestic buildings.
Government publishes plans to 'build back greener'.
The contentious nature of claims associated with cladding, fire safety and EWS1 forms.
ECA comments on low-carbon heating systems initiative and Heat and Buildings Strategy.