Slumping typically isn’t what we consider a ‘good’ thing in everyday life. If you’re prone to slumping and often experience a sore back because of it, you should probably go see a physio. They’re the ones who help with this kind of ‘slump’.
But in the world of foundation and construction, slumping can actually be a positive. If you’re wondering why pile foundation for your building requires a higher slump value than other applications, the experts at Techniblock explain everything you need to know in this post.
What is ‘slump value’?
The ‘slump value’ of pile foundation refers to the consistency of fresh concrete before it sets. The higher the slump value, the more fluid the concrete is; the lower the slump value, the thicker it is.
The term ‘slump’ originates from the test we use to measure its consistency. The test is done by filling a cone with a sample of the concrete, removing the cone, and measuring how far the concrete has slumped.
Slump classes explained
There are 5 slump classes when measuring the slump value of your pile foundation, or just cement in general.
- S1, with a slump range of 10-40
- S2, with a slump range of 50-90
- S3, with a slump range of 100-150
- S4, with a slump range of 160-210
- S5, with a slump range of 210-N/A
S1 is the lowest slump value class, and is quite thick, making it suitable for kerb and pipework bedding. On the higher end of the scale, around S4 and S5, is the higher slump value concretes. These are the ones that are ideal for pile foundations, slabs and more.
Higher slump values and why they’re ideal for concrete
When laying a slab for your home, you’re laying out a lot of concrete that needs to be spread a long way. If the concrete is a low slump value, it will be quite thick, and will be hard to spread evenly across the surface to create your slab. That’s why it needs to be more fluid in consistency – so that it can flow around the steel for a better compaction.
Consequences of using concrete with too high a slump value
Using pile foundation concrete that has too low a slump value will result in:
- Uneven pile foundation
- Honeycomb effect, in which gaps are formed
- Weak, ineffective foundation
Concrete with a high slump value should only be left in the hands of experienced professionals like the guys at Techniblock. Techniblock are Victoria’s leading team in foundation construction and repair. They’ve built Melbourne foundations since 1989, having established themselves as specialists in other areas like repairs, underpinning and basement construction.