Various types of water-reducing agents are available on the market. They vary in their molecular structure. These substances are added to cement to make it more workable. Their effect on concrete strength depends on their dosage and their application. Some of them are also used in patching concrete.
Polycarboxylate superplasticizer (PCE) is one of the common water reducing agents. It has high water-reducing rate. It is used to produce pumpable concrete. It is an organic electrolyte and belongs to polymer surfactant. It is spray dried. It is mainly used in cement concrete.
It is also used as an anti-adsorption ingredient. It is effective to reduce the permeability of the concrete and improve its durability. It has a strong charge repulsion and longer main chain. It can be mixed with other ingredients to form a mixture. The finished water-reducing agent should be free from impurities. It can be applied in different types of paste materials.
Microsilica admixtures can be added in both dry and slurry form. They can be used to make waterproof mortar and increase the compressive strength. These admixtures also meet the low permeability requirements.
The compatibility of the superplasticizer with the cement depends on the calcium sulfate content in the cement and the reactivity of C3A. It is also affected by many other factors. In addition, the amount of the admixture should not be too high. Moreover, the fluidity of the concrete should be checked.
The best superplasticizer for concrete should be non-explosive and safe to transport. In addition, it should be used in high-performance concrete.