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Correct compaction is probably one of the most important work steps in conventional concrete. Because only carefully compacted concrete has no defects. This also ensures that the concrete will still have the required properties years later. To conclude this guide on, we would like to go into the most important aspects of self-compacting concrete.

3.1. What are the differences between self-compacting and light-compacting concretes?

So-called self-compacting concrete was developed and used in Japan as early as the late 1980s. This meant one revolutionary advancement of conventional concrete. Our tabular overview shows how self-compacting concrete differs from light-compacting concrete.

Lightly compacting concrete (LVB)
  • Lightly compacting concrete (LVB) is used when only a very low vibration energy has to be used for compacting
  • Lightly compacting concretes belong to consistency classes F5 and F6
  • They have a high flour grain content and do not exceed the maximum limit of DIN 1045
Self-compacting concrete (SCC)
  • If no compaction measures at all are required, the concrete is referred to as self-compacting (SCC)
  • self-compacting concrete exceeds the maximum limit of DIN 1045

3.2. What are the advantages and disadvantages of self-compacting concrete?

Self-compacting concrete is also used in bridge construction due to its high strength.

No compression measures are required with SVB. They vent independently by gravity alone. This process is made possible by the use of modern high-performance concrete plasticizers based on polycarboxylate. This is how he instructs very good flow behavior and flows almost by itself to the level compensation - this also over long distances.

Thanks to these extremely good flow properties, even the most demanding formwork geometries can be filled without any problems. After the formwork has been removed, a almost pore-free concrete surface. With conventional concrete, these desired properties can only be achieved through careful compaction.

Another benefit of self-compacting concrete is its extremely high strength, which means that it is also used, for example, in bridge construction. It does not show any nests on the concrete surface. In addition, SVB has a uniform concrete quality with very good durability.

The elimination of compaction saves a considerable amount of time. In addition, the layer-by-layer concrete installation with corresponding pouring heights of 50 cm, which is otherwise common on construction sites, can be completely dispensed with.

Since the Noise from the vibrator is eliminated, this is another important advantage for construction projects in densely populated residential areas or in closed halls. This means that concreting can take place overnight, for example, without bothering third parties.

Danger: A disadvantage of the SVB is the higher price. There are also risks associated with approval.

3.3. In which areas is SVB used?

If the use of a vibrator is not possible, self-compacting concrete is used.

Self-compacting concrete is mainly used when the use of a conventional vibrator is not possible. This can be a dense reinforcement or a complicated and unfavorable shape of the components, which so insufficient venting enable.

The very good flow properties of the SCC, however, make it possible to embed the reinforcement perfectly without any problems.

This advantage is also used in the manufacture of precast concrete parts. Due to the uniform and pore-free surface, self-compacting concrete is predestined as a ideal building material for exposed concrete walls or for concrete walls and floors with particularly high visual requirements.

Thanks to the material properties outlined above and its advantages, self-compacting concrete not only covers special areas of application, but complements conventional concrete as high-strength concrete in its area of ‚Äč‚Äčapplication.

You can find more information on the subject in the following articles on Painting concrete and calculating concrete fall.

Photo credits: Adobe Stock / Shuttershudder, Adobe Stock / Shuttershudder, Adobe Stock / Bernd Fuelle, Adobe Stock / Fult, Adobe Stock / GCapture, Adobe Stock / maykal, Adobe Stock / Otto Durst (chronologically or according to the order of the images used in the buying guide sorted)