How Are Concrete Additives Classified in Ukraine? Standard EN 934-2:2019.

Concrete additives are an important part of the technological process of preparing concrete mixtures, allowing for the achievement of the necessary properties of the material. In Ukraine, the DSTU EN 934-2:2019 standard is used, which defines the classification of additives for concrete and building mortars. In this article, we will examine the main types of additives, their functionality, and their importance in construction.

What are Concrete Additives?

Concrete additives are products added to the concrete mix in amounts not exceeding 5% by weight of the cement. Their main purpose is to modify the properties of the concrete mix or the finished concrete. They can regulate consistency, accelerate or slow down hardening, improve frost resistance and water retention, and also impart special properties to the concrete.

Classification of Concrete Additives According to DSTU EN 934-2:2019

The DSTU EN 934-2:2019 standard classifies concrete additives based on their primary functions, taking into account their effect on the characteristics of concrete mixtures.

Water-Reducing / Plasticizing Additives

Water-reducing / plasticizing additives are those that reduce the amount of water in the mix without changing its consistency or, conversely, improve the slump and flow of the mixture without changing the water content. They help improve plasticity and reduce the water-cement ratio.

High-range water-reducing / superplasticizing additives significantly reduce the water content of the mixture or substantially increase its plasticity while maintaining consistency.

Additives That Affect Hardening

• Set accelerating additives — reduce the time required for the mixture to transition from a plastic to a solid state.
• Set retarding additives — extend the hardening time of the mixture, which is particularly important in high temperatures or when transporting the mix.

Additives for Improving Water Retention

• Water-retaining additives — reduce water and solution separation from the mix, helping to maintain its stability during storage.

Air-Entraining Additives

• Air-entraining additives — introduce a controlled amount of air into the mix, which helps to create air pores in the concrete after it hardens. This increases the frost resistance of the concrete and its thermal insulation properties.

Viscosity Modifiers

• Viscosity modifiers — added to limit segregation of the mix by improving cohesion and ensuring its stability during preparation and transportation.

Combined Effects

• Combined additives — are additives that have a dual effect. For example, water-reducing / plasticizing additives with set retarding combine the effects of reducing water and improving plasticity with an extended setting time.

Hydrophobizing Additives

• Hydrophobizing additives — reduce the capillary absorption of the concrete, improving its water resistance.

Importance of the Standard in Ukraine

DSTU EN 934-2:2019 is an important standard for regulating the quality of additives used in concrete throughout all stages of construction. This standard helps ensure the high quality of concrete mixtures and their properties meet the requirements of modern construction.

How to Choose Concrete Additives?

When choosing additives for the concrete mix, it is important to consider:

• Type of concrete mix: Different additives are suitable for different types of concrete (e.g., ordinary, pre-stressed).
• Operating conditions: For example, in wet or aggressive environments, additives that improve water retention and corrosion resistance should be used.
• Temperature conditions: For concrete working in high or low temperatures, additives to improve hardening or slow the setting process may be needed.

Conclusion

The correct choice of concrete additives, regulated by DSTU EN 934-2:2019, can significantly improve the properties of concrete mixtures and their final products. They ensure the durability and high reliability of concrete structures.

One of the leading suppliers of concrete additives in Ukraine is Koalida LLC, which operates under the brand MTC Concrete. The company provides high-quality additives for concrete mixtures that comply with the highest

international quality standards. With MTC Concrete, you can ensure the reliability and durability of your concrete structures.