A foundation is crucial for the long life of the building or the structure. A strong foundation supports the weight of the structure built above it. If a foundation is strong enough to support the building, then the life and strength of the building can increase.
For a robust foundation, stabilizing the basement is a vital process. For this purpose, sands are used. In this blog, let us explore the importance of sand filling in foundation, the types of sand used in the process, and the detailed procedure and application.
What is Sand Filling in Foundation?
Sand filling is the process used to fill the gaps in the base structure, helping to create a stable platform for constructing a building. It can provide strength to the structure to withstand natural calamities. Leveling the basement is essential to build a structure above it.
If your leveling is perfect, it gains the ability to bear the weight placed upon it, thus increasing the load-bearing capacity of the soil. The sand that is used to fill the gaps should be clean and coarse to attain the best leveling surface. This filling process can be done in different layers to ensure the density and stability of the basement.
Importance of Sand Filling in Foundation
Sand is known for its gritty texture and coarse particles when you rub it in your hands. These coarse fine particles are compatible. If you compact it at high density, sand provides better grip and support for the foundation. They are also perfect for providing strength, stability, and physical support.
Soil Stability
Soil stability refers to the capacity of the soil to limit the erosion of soil by wind or water. Sand is made up of a variety of particles that include silica and other elements. The stability of the soil lies in its bounding nature, which prevents it from breaking apart when exposed to external factors such as wind and erosion. Ensuring the stability of the soil is important for areas that are naturally having loose soil or active soil erosion.
Improving Load-Bearing Capacity
The compact filling of the sand in the foundation provides physical support to the above-constructed building. It increases the load-bearing capacity of the columns and thus evenly distributes the weight to the structure. It also reduces the stress on the soil by balancing the weight throughout the building.
Preventing Water Accumulation
The collection of water below the foundation is a risky issue. It leads to soil erosion, weakened foundations, and structural damage. To avoid these situations, sand filling is used. A drainage layer is created below the foundation to prevent the collection of water under the foundation.
Mitigating Differential Settlement
Differential settlement happens when the soil below the foundation may shift, expand, or contract irregularly. It may cause cracks in the wall or floor, or can form more gaps in the building structure. This can be stopped by sand filling in the foundation. You must check whether the sand is filled evenly at every corner of the foundation to ensure the stability and stiffness of the basement. Sand-filling minimises uneven settlement and enhances the stability and stiffness of the soil.
Reducing Soil Shrinkage and Swelling
Soil shrinkage and swelling mainly happen due to the moisture content in the soil. Soil naturally contains moisture in it. Soil shrinkage and swelling can be prevented by sand filling in the foundation. The compact sand filling doesn’t allow the moisture to interact with the soil. Sand-filling protects the foundation from moisture-related issues by reducing moisture in the soil.
Types of Sand Used in Foundation Filling
Coarse Sand
Due to its excellent drainage properties, coarse sand is used for filling the foundation. The fine and compact layer of these large particles provides a stable basement for a solid foundation.
Fine Sand
Fine sand is comprised of smaller particles and is used for giving a smooth finishing surface. It can be mixed with coarse sand to provide a stable foundation.
River Sand
River sand is sourced from the riverbed. It is known for its pure and smoothness which is ideal for filling in the foundation.
Manufactured Sand
It is commonly called M-sand. This industrial-manufactured sand is used as an alternative to river sand. These are made from breaking of larger rocks and processed for suiting construction works.
Best Practices for Sand Filling in Foundation
The best practices for sand filling in the foundation include several processes. They are as follows:
1. Soil testing
Soil testing is crucial for determining the quality and type of soil. It helpsin selecting the appropriate soil to be used in the foundation and in establishing the necessary thickness of the layers for optimal foundation strength.
2. Layer-by-layer compaction
Usually, sand filling is done layer by layer process. Each layer is compacted to ensure that the sand particles are tightly packed and provide the utmost strength to the building.
3. Use of water
In the sand-filling process, water is used to wet the layer to give extra bindness and strength to the foundation. But be careful to avoid over-wetting, which could lead to mud creation, which could weaken the foundation.
4. Proper drainage
Proper drainage is important to avoid collection of water below the foundation. This can be prevented by using drainage pipes to enhance the drainage properties of the sand.
5. Regular soil inspection
Regular inspection is needed to check the stability of the soil that is ready for building construction.
Why do we Need Sand Filling Under Foundation Footings?
Sand-filling in the foundation footings is a vital process to provide stable soil. Some important benefits are as follows:
- Sands are filled to provide uniformity to the basement.
- To ensure the structural stability of the construction.
- Sand filling protects the building from termite attack
- Helps to avoid the structure directly in contact with the foundation soil.
- To increase the compact nature of the soil.
Conclusion
On the whole, sand filling is an important process in laying the foundation. It forms a compact layer and strengthens the stability of the soil for its longevity. The overall success of the construction project lies in the sand-filling process.