Foundations are the base of any building structure. sometime a single shallow or deep foundation is not enough for the building therefore a combination of two foundations is done to enhance the support and stability. One foundation that has become more common and useful is the pile raft foundation. Let’s learn about what a pile raft foundation is and how it benefits you.
What is a Pile Raft Foundation?
A pile raft foundation is a combination of a raft and a pile foundation. It’s a hybrid structure consisting of piles and reinforced concrete rafts to provide super stability and distribute weight evenly across both foundations.
It is a combination of both shallow and deep foundations. The raft is placed beneath the building footprint, followed by a number of reinforced piles. This type of foundation is usually done for high rise buildings and skyscrapers where the soil is unable to support excessive weight and there is a risk of uneven settlement.
Raft Foundation
Raft foundations are shallow foundations that spread the weight of the building to a wider area. It is also known as a mat foundation. This type of foundation is often used for domestic projects.
Pile Foundation
Pile foundations are a type of deep foundation where vertical structural elements are drilled into deeper parts of the soil and installed into the ground to provide a stable structure. This type of foundation is used in areas where the upper part of the soil is poor and unstable.
Benefits of Pile Raft Foundation
The following are the benefits of a pile raft foundation:
- By combining the raft and pile foundation it allows for better stability and can supports heavier loads. The load is distributed on both foundations. This helps prevent the building from having uneven settlement.
- This foundation doesn’t require any kind of extensive excavation and soil replacement. This makes it cost-effective as the existing soil is utilised and used.
- This foundation is also good in poor soil conditions where a traditional foundation is not suitable for construction.
Disadvantages of Pile Raft Foundation
A pile raft also brings some disadvantages. Some of the disadvantages are as follows:
- Building a pile raft foundation is not an easy task. It requires experts to ensure it has a stable structure. This can also lead to a construction delay.
- This foundation can affect the environment. Piles need to be drilled into the ground to be installed. Drilling can cause instability in the environment.
- While this foundation is cost-effective in the long run, it has high installation costs.
Construction Process of Pile Raft Foundation
When you are constructing a project using a pile raft foundation, the following steps are involved:
Site Assessment
A thorough investigation is done on the site to assess the condition of the bearing capacity, ground condition, and settlement characteristics.
Foundation Design
After the investigation of the site is done, a design layout is made for the arrangements of piles and raft slab to ensure the stability and meet the requirements of load bearing.
Pile Installation
Piles are installed depending on the soil and project conditions and specifications.
Raft Installation
After the piles are placed in the ground, a concrete raft slab is constructed by connecting all the piles, which provides a stable platform for the construction of higher buildings.
Conclusion
Pile raft foundation is a combination that provides extra stability and durability, resulting in a much better option for constructing skyscrapers. Constructing a building is not a small investment, and you should make sure that your building foundation is perfect to ensure a longer performance and stability. When doing a construction project, it is essential to always consult an expert in order to know what kind of foundation you should use.
