Additifs légers pour béton | Agents moussants haute performance pour béton cellulaire
Un superplastifiant est une substance ajoutée à un produit ou à un matériau pour augmenter sa plasticité.. Cela peut réduire la teneur en eau et rendre le produit plus doux. It can also increase the durability and strength of the product.
Superplasticizers are used as an admixture to improve the quality and durability of concrete. They can help in improving the flowability of concrete, preventing the segregation of particles in a suspension, and delay setting of cement. They can also help in reducing the permeability of concrete.
Some superplasticizers are synthetic and some are natural. They are often based on lignosulphonate. The molecules of a superplasticizer are hundreds of times bigger than the molecule of water.
They are typically used to reduce the amount of water required in a concrete mixture. They can reduce the water-to-cement ratio, which can increase the strength and durability of the concrete. They can also reduce the shrinkage of concrete and can prolong the hydration process. They can also help in controlling the temperature of concrete in large volumes.
They are also often used as an auxiliary in plasters, produits de beauté, and cleaning agents. They are commonly added to cement at about 0.5-0.3% of the weight of the cement. They are also used as an auxiliary in the production of plastic products.
The dosage of a plasticizer is determined by a Marsh Cone Test. It can vary from five to twenty liters of plasticizer per cubic meter of concrete. It is usually mixed during the mixing process and during the site pour.