Concrete water reducer refers to an admixture that can reduce mixing water consumption and increase concrete strength under the conditions of constant workability and cement consumption, or save cement consumption under conditions of constant workability and strength.
Classification of Concrete Water Reducer
Water reducing admixtures are usually divided into: lignosulfonate water reducer, naphthalene based superplasticizer, melamine-based superplasticizers, sulfamate-based superplasticizers, fats family superplasticizer, polycarboxylate superplasticizer.
The Function of Water Reducing Admixture
The use of water reducing admixtures can save cement, reduce costs, shorten the construction period, improve the construction of concrete, and increase the quality and service life of buildings. It is of great significance in terms of energy saving, environmental protection, engineering economy, labor protection, etc. Its uses are mainly reflected in:
(1）Without changing the ratio of various raw materials (except cement) and the strength of concrete, the amount of cement can be reduced. Adding 0.2%-0.5% of cement quality concrete water-reducing agent can save more than 15-30% of the amount of cement.
(2) Without changing the ratio of various raw materials (except for water) and the slump of concrete, reducing the amount of water can greatly increase the strength of concrete. By reducing water, high-strength concrete of C100 can be poured.
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 self-flowing, pumping, and without vibration, which can increase construction speed and reduce construction energy consumption.
4)Adding concrete superplasticizer can increase the life of concrete by more than one time, and prolong the normal service life of buildings by more than one time; reduce the shrinkage of concrete solidification, prevent cracks in concrete components, and improve frost resistance, which is beneficial in Winter construction.
Development Status of Concrete Water Reducer
The development of international water reducing admixtures has gone through three stages: the first-generation general water reducing admixture stage represented by wood calcium, the second-generation high-efficiency water reducer mainly represented by naphthalene series (mainly naphthalene sulfonate series, sulfonated melamine series, aliphatic series, sulfamate series, etc.) stage and the third-generation high-performance water reducing admixture stage represented by polycarboxylic acid series. At present, the domestic water reducer market is dominated by second-generation water reducers with three-generation water reducer coexisting, and the market share of polycarboxylic acid-based water reducing admixtures is increasing year by year.