Concrete foundations are essential for the construction of new structures, providing the support they need. The aim is that the structure, such as a building or bridge, will transfer its load into layers of rock and soil which have the right characteristics to support it. But what are the different types of concrete foundations?
Importance of Good Foundations
The foundations created are vital to safety and structural support. Different types of concrete foundations will be suitable for various applications, and there are many considerations you must take when choosing the right one for the job. Good foundations are selected after identifying the ground conditions and the load which needs support. The space available is also a key factor to look at, and the type of stress the structure and foundations will be under (such as vibrations), and whether they will withstand the effects. Most types of foundations fall into two main categories (although there are many subcategories too) – shallow and deep.
Shallow foundations are typically used for domestic projects such as kerbsides, walls and steps. They’re the type of foundations used where the surface support available is considerate enough for the load of the structure. Types of foundation landing in this category are footings (e.g. strip foundations for walls), raft foundations (e.g. for wider areas such as buildings) and pad foundations (e.g. for columns).
Deep foundations are required where the surface soils are not adequate to support the structure’s load. Deeper layers will need to be sought for the foundations which have a higher load-bearing capacity. A high strength concrete will be used for these. Applications for foundations falling under this category include piling projects, such as concrete columns made from reinforced concrete and may require the use of steel. Pile foundations may also be needed for walls which need deep trenches created. Another type of deep foundations are caissons, suitable for structures being built below water level, such as bridges.
Using the Right Concrete Strength
When choosing the type of foundations for a project, the right strength of concrete must also be used. For shallow foundations, a lower strength mix can often be chosen, such as C15/Gen 2 concrete for step foundations, C20/Gen 3 for slab foundations or C25 for footings. However, for construction projects, much higher strengths of concrete are necessary. For example, C40 is one of the most commonly used, where traffic will be present on the surface. However, for anything where the highest level of support is key, there are some exceptionally strong mixes such as C50, C55 and C60 available. Speak to an expert about what you need.
Need concrete for foundations?
At Maguire, we supply a wide range of concrete mixes, suitable for all jobs. Our team are happy to advise about the type of concrete you need, whether it’s for a domestic or commercial project. We work across London and Surrey locations, such as Leatherhead, Whyteleafe and Warlingham. Call now on 020 8648 7688 for free advice and a no-obligation quote.