High range water reducers (Super plasticizers) - types, application, effects, advantages | special concrete

High range water reducers (Super plasticizers)

High range water reducers (Super plasticizers)

          The water content (Water cement ratio) is influence a major role in concrete strength. Low water cement ratio gives more strength to the concrete but the major impact is workability. Concrete should be more workable as much as possible. Increasing in water content leads to strength loss. The only way to increase the workability and strength subsequently is usage of high range water reducers or super plasticizers.

Types

• ·        Sulfonated melamine-formaldehyde condensates.
• ·        Sulfonated naphthalene-formaldehyde condensate
• ·        Modified lignosulfonates.
• ·        Polycarboxylate derivatives.

Effects in concrete Properties

• ·        It improves the workability of concrete without bleeding and segregation
• ·        It increases the compressive strength of concrete
• ·        Shrinkage of concrete is reduced
• ·        If properly cured, permeability of concrete in which high range water reducing admixture is used is greatly reduced, in turn, penetration of aggressive agents is declined.
• ·        Bond strength of concrete also increased

Advantages

• ·        High range water reducers may serve the purpose of increasing strength through a reduction in the water-cement ratio while maintaining equal slump, increasing slump while maintaining equal water-cement ratio or a combination thereof.
• ·        It declines concrete permeability and increase its durability.
• ·        High range water reducing admixture decreases the quantity of cement needed to gain specific strength.