+36 30 250 855
How does Denka CSA#20 work?
Denka CSA #20 is a swelling calcium sulfoaluminate-based cement additive that exerts its effect chemically. During its hydration, it creates ettringite, which results in a rapidly forming, swelling and pore-reducing crystal structure. During the setting of the cement paste, colloidal crystals continue to grow and fill the voids of the already formed crystal skeleton.
Therefore, this method is fundamentally different from the aluminum powder shrinkage reduction method that is accompanied by gas formation, the effect of which occurs in a very short time, typically before the increase in the strength of the paste.
Advantages of Denka CSA#20
Reduces the shrinkage of concretes and mortars, primarily autogenous shrinkage Reduces the pore volume of concrete Increases the flexural-tensile strength of concrete Can also be used together with fast-setting calcium aluminate cements.
Dosage
The recommended lower limit of dosage is usually 5, in the case of optimal dosage, 8 - 15% of the weight of the cement (depending on the recipe). Overdosing Denka CSA#20 can lead to excessive volume growth and even a decrease in strength, and can also increase the sensitivity of concrete to freeze-thaw effects. Denka CSA#20 should be added to the mixer after the cement, before adding water, and mixed until the material is thoroughly mixed. Denka CSA#20 does not have a setting accelerator effect.
The most common areas of application for Denka CSA#20 are:
Quality:
Denka CSA#20 is a cement additive containing high-purity clinker, which has a quality certificate.
Packaging:
Multi-layer, high-quality 25 kg bags containing plastic film on a 1,000 kg pallet, 1,000 kg Big Bag, and in bulk.
You can find the technical data sheets of the products here.
