Concrete setting accelerators are a type of additive that shortens the duration of the setting process, resulting in significant time savings in construction.
To explore this and other advantages, we will describe the types of accelerators, their applications and benefits, as well as the advantages of automating the concrete production process using these additives.
A setting accelerator acts in the opposite way to a retarder.
What they have in common is that, in both cases, the additives modify the rate of cement hydration depending on the desired properties and the project requirements.
In the case of accelerators, the additive works by increasing the reaction speed of the cement particles, so they can hydrate in the shortest possible time, thereby accelerating the setting to the desired time.
Accelerating additives can serve two purposes: reducing setting times and increasing the strength of the concrete.
They offer the following benefits: :
Although there are different types of accelerators, they are generally classified based on their salt composition (fluorides, bromides, hydroxides, chlorides, nitrates, nitrites, and carbonates), with the main classification criterion being whether they contain a chloride ion.
The difference lies in the fact that chloride-based accelerators can be more effective, but they may also cause steel corrosion when certain concentrations are exceeded.
For this reason, ACI 318 specifies allowable levels of this type of additive depending on the type of reinforced concrete being used, considering the project characteristics, the type of material, and whether it is exposed to moisture.
Since multiple factors influence the concrete setting time—such as dosage, type of cement, temperature of raw materials, ambient temperature, and the volume of concrete being poured—it is recommended to conduct a trial mix in a laboratory using the materials and conditions of the actual project. This helps determine the necessary dosage of the additive to achieve the required setting acceleration.
On the other hand, the effectiveness of a non-chloride concrete accelerator lies in the fact that its main component, nitrates, does not promote corrosion. Therefore, in countries like Japan and the United States, they are also used as corrosion inhibitors.
In conclusion, it can be said that both chloride and non-chloride accelerators work differently, but both produce the same setting effect when required by the project specifications.
Concrete production is a fundamental activity in construction, as it is an essential material for creating durable and safe structures and infrastructure. Optimizing concrete production with setting accelerators can offer a range of significant benefits that can make a difference in the efficiency and quality of the production process.
The use of setting accelerators can significantly improve the setting speed, reducing the waiting time required for the concrete to reach the appropriate strength for use.
In addition, accelerators can also enhance concrete quality by reducing the amount of trapped air in the mix, improving compaction, and increasing the material’s long-term strength.
To achieve the best results in concrete production with accelerators, it is essential to have the right tools and techniques. Specialized software like Arkik can help accurately dose the accelerating additives and control the production processes to ensure more efficient production and superior quality of the resulting concrete.
