Concrete is being used in buildings, investment properties, and so on. Usually integrated among the elements that make up concrete, admixtures act on the main characteristics of the material. These chemicals transform the consistency of concrete and disrupt its conversion process. They exist in many varieties and are used in different contexts. Take a look at this concrete admixture of Malaysia with us.
What are concrete admixtures?
These are chemicals commonly added to the ingredients that make up concrete. Having become essential in the making of this work, this tool has the merit of upsetting the quality of the mortar and of adding additional properties to it. It constitutes only a small dose of the mass. And their use can considerably modify the setting time, and alter the seal of the product.
Why add an admixture to concrete?
Admixtures are chemicals that are added to concrete in low doses (less than 5% by volume) will modify their properties in the fresh or hardened state. They are added at the time of mixing.
Adjuvants are classified according to their effects:
- Setting retarders or accelerators.
- Plasticizers which increase the workability of fresh concrete.
- Water repellents that are waterproof.
- The air coaches.
- Curing products that protect concrete during hardening.
- Grinding agents.
- Use of concrete set retarders
- They slow down the setting by delaying the hydration of the concrete.
They are useful in hot weather to prevent concrete from hardening too quickly or when transporting concrete over long distances. When the conditions of setting up are difficult or long, they make it possible to carry out this one or to make recovery more easily.
Use of concrete setting accelerators
They work by accelerating the hydration of the concrete. They are of two kinds: setting accelerators or hardening accelerators. Note that their use may result in lower mechanical resistance of the concrete.
Use of plasticizer for concrete
They facilitate the laying of concrete by making it more manageable. The water-reducing plasticizers give it better resistance.
Superplasticizers, which are synthetic polymers, have a greater action than traditional plasticizers for less product. Some are specifically designed for self-leveling (BAN) or self-leveling (BAP) concrete.
Use of water repellents for concrete
They make it possible to waterproof concrete by stopping capillary absorption. They are more suitable for use in coating plasters rather than in all concrete.
They are of two kinds: the bulk water repellent which is incorporated into the mixture when mixing concrete or the surface water repellent which is applied to hardened concrete. In the latter case, the water repellent is no longer really an adjuvant.
Their role is to create microscopic air bubbles in the concrete. They allow it to better resist freezing and especially freeze/thaw cycles.
They are not strictly speaking admixtures since they are sprayed on the concrete once it is poured. They prevent or compensate for too rapid moisture loss and control the temperature of the concrete. Too fast-drying leads to the lower mechanical resistance of the concrete and shrinkage or cracking phenomena.
They are added during the manufacture of cement at the time of grinding. They prevent the cement from sticking together and ensure a better quality of the finished product.
Did you know? The addition of admixtures in the concrete dates from Roman times. Egg yolk or blood was then added to the lime concrete. As early as the development of concrete in the 19th century, various attempts to add admixtures were carried out. Until attempts to add sugar as a setting retarder!