19/08/2024
Foundation settlement and how it affects our buildings.
Let's delve deeper into SOIL COMPACTION and see how it can cause foundation settlement.
Soil compaction simply means the removal of pores in soil used to fill your foundation to create a denser layer (rock-like) platform for the building to sit on which is done by compressing the filling materials.
It occurs when soil particles are pressed together to reduce the air space between them.
The common term used is “FILLING.” The act of pouring sand into the foundation to create a smooth surface for oversite concrete/ floor casting.
The purpose of soil compaction is to help the soil to support the building.
Soil compaction is like pregnancy, whether you conceal it or not, it’ll manifest.
Many people after filling their foundation, rush to do oversite concrete without ensuring proper soil compaction. If you don’t compact the soil, what will happen is that, a hollow layer will be created between the soil and the building, and this will cause foundation settlement.
That’s the reason behind cracks in walls, tiles removal, tilted doors and windows, making it difficult to freely open and close, cracked slabs etc.
We can demonstrate this by fetching sand of equal volumes into two separate containers.
✅ When you press down the sand in container A,🫙 you’ll observe the level will decrease. If you want the container full, you’ll have to top up with more sand. You’ll repeat this process until the container can’t take anymore sand. The soil becomes dense and hard. This is the point where you can say the soil is properly compacted, and can hold the weight of the structure.
✅ However, in the second container 🫙, you’ll equally observe that the container is full. Nonetheless, if you put any item of significant weight into it, you’ll notice the object will sink.
The essence is that, the soil in container B isn’t compacted; it has a lot of air and pores in them, making it less dense, and more prone to foundation settlement. Water can easily pass through it, and you know what will happen.
You don’t want water to compromise anything under your home and cause damage.
It is the same story with building on poorly compacted soil.
The whole point is to make the soils dense so water doesn’t break in or navigate through and cause erosion.
How do I ensure proper soil compaction?
1. If you’re not in a hurry to complete your project, then leave your foundation to settle by itself. When you do the filling, allow time to pass, and let rain and sun do the magic.
Do you realize that when you fill your foundation to the brim, and it rains over time, the filling drops, and you’ll have to top up again and again? Yes! That’s the natural way of ensuring proper compaction.
2. If you’re in a hurry to complete the project, there are compaction machines available. Hire one and use it. The practice where your mason lifts blocks and drops them hard on the filling won’t achieve any desired results. Others will join pieces of wooden boards and pound the soil like fufu. I’m sorry that’s just on the surface. Do the right thing.
That is why we have rammer machine Yusadak Structures to ensure the compaction is done well.