For those who’ve never heard of them, pile foundations (as the name suggests!) use what are known as “piles” — long beams made from wood, steel, or concrete that are driven firmly into the ground — as substructures in order to support the buildings which get to be built on top of them. These foundations are regularly utilised in marine construction for things such bridges, piers, embankments, docks, oil rigs, and wind farms. They are also usually applied where the soils will not support other foundation types, and for supporting a load that would be overly heavy for other kinds of traditional construction.
Down the ages, the beams that were used in pile foundations before the 19th Century, were made from wood. Wood piles were the type that had been in use for all known recorded history. After the turn of the 19th century, steel piles were produced, and in the 20th century, concrete was developed and became widely available. Both of these materials have certain advantages and disadvantages, and the two of them are still used up to the present day in this kind of construction.
Putting Piles into Place
Pile foundations are driven into place by piling contractors you can trust, with a pile driver, which is a heavy piece of equipment that lifts a heavy a weight to a certain height and then releases it forcefully onto the top of the pile. This weight pushes and forces the pile down into the ground and will be repeated until the correct depth has been achieved. Steel is notably easy to drive into the ground in this manner, whereas driven concrete piles have to be particularly reinforced so as to withstand all the hammering from the weight.
Another method is where piles can be drilled and poured in place to create a similar type of foundation. This is usually carried out in places where pile driving may not be so practical, as in somewhere where there is a low headroom. Drilling is also applied for the constructing of pile foundations in an area where the soil is very dense or hard.
Putting a Cap on it
After all of the beans have been put into place for a pile foundation, what is known as a “pile cap” is then fitted over them. The cap will then act to transfer the weight of the construction above it to all of the members below, which supports the entire building by gently absorbing its load, and is thus transferred to the deep subsurface upon which they rest, as well as the soil which surrounds the pile.
Occasionally, what are known as “grade beams” are connected straight to the tops of piles. In such pile foundations, the load of the building is transferred through the grade beam to the piles. You will often see this type of foundation on pier construction.
And now you’ll never look at a building the same way again!