Post Date:9, Sep, 2024
Water reducer is a concrete admixture that can reduce the amount of mixing water while maintaining the slump of concrete. Most of them are anionic surfactants. After being added to the concrete mixture, it has a dispersing effect on cement particles, which can improve its workability, reduce the unit water consumption, and improve the fluidity of the concrete mixture; or reduce the unit cement consumption and save cement.
According to the appearance:
It is divided into water-based and powder-based. The solid content of water-based is generally 10%, 20%, 40% (also known as mother liquor), 50%, and the solid content of powder is generally 98%.
According to the ability to reduce water and enhance strength:
It is divided into ordinary water reducer (also known as plasticizer, with a water reduction rate of not less than 8%, represented by lignin sulfonates), high-efficiency water reducer (also known as superplasticizer, with a water reduction rate of not less than 14%, including naphthalene series, melamine series, aminosulfonate series, aliphatic series, etc.) and high-performance water reducer (water reduction rate is not less than 25%, represented by polycarboxylic acid series water reducer), and is divided into early strength type, standard type and slow setting type respectively.
According to the composition materials:
Lignin sulfonates, polycyclic aromatic salts, water-soluble resin sulfonates, naphthalene-based high-efficiency water reducers, aliphatic high-efficiency water reducers, amino high-efficiency water reducers, polycarboxylate high-performance water reducers, etc.
According to the chemical composition:
Lignin sulfonate water reducers, naphthalene-based high-efficiency water reducers, melamine-based high-efficiency water reducers, aminosulfonate-based high-efficiency water reducers, fatty acid-based high-efficiency water reducers, polycarboxylate-based high-efficiency water reducers.
The role of water reducer:
1.Without changing the ratio of various raw materials (except cement) and the strength of concrete, the amount of cement can be reduced.
2.Without changing the ratio of various raw materials (except water) and the slump of concrete, reducing the amount of water can greatly improve the strength of concrete.
3.Without changing the ratio of various raw materials, the rheology and plasticity of concrete can be greatly improved, so that concrete construction can be carried out by gravity, pumping, without vibration, etc., to increase construction speed and reduce construction energy consumption.
4.Adding high-efficiency water reducer to concrete can increase the life of concrete by more than double, that is, extend the normal service life of the building by more than double.
5.Reduce the shrinkage rate of concrete solidification and prevent cracks in concrete components; improve frost resistance, which is conducive to winter construction.
Mechanism of action of water reducer:
·Dispersion
·Lubrication
·Steric hindrance
·Slow-release effect of grafted copolymer side chains
Post time: Sep-09-2024