Frequently Asked Questions

Does the air entrained by Cebex 112 reduce the compressive strength of the concrete?

At the dosage range of Cebex 112, the controlled air entrainment (typically 1 to 3% additional air by concrete volume) provides a workability improvement that can be used to offset a small reduction in the water content. If the water content is reduced by an equivalent amount to compensate for the workability improvement, the net effect on strength is minimal or slightly positive. However, if Cebex 112 is added without reducing the water content, the additional air may cause a slight strength reduction (typically 2 to 5 MPa for each 1% of additional air). For structural concrete where the design mix has specified minimum strength requirements, the dosage of Cebex 112 should be established by trial mix to confirm that the 28-day strength target is maintained.

Can Cebex 112 be used in combination with other Conplast superplasticisers?

Yes. Cebex 112 is compatible with most Conplast and Auramix superplasticisers and can be used in combination for applications where both workability improvement (from the superplasticiser) and improved cohesion and reduced bleeding (from Cebex 112) are needed. A common example is pump concrete where the superplasticiser provides the required slump for pumping, and Cebex 112 provides additional cohesion to prevent the mix from segregating in the pump line. Add each admixture separately to the mixing water — do not pre-mix them together in concentrated form. The combined dosage and effect should be confirmed by trial mix before production.

Is Cebex 112 the same as an AEA (air-entraining agent)?

Cebex 112 provides a dual function of workability improvement plus controlled air entrainment, which has some similarities to an AEA, but it is not the same product as a dedicated air-entraining agent. A dedicated AEA (such as Conplast AEA) is designed primarily to entrain a specific controlled volume of air (typically 4 to 7% for freeze-thaw resistance) with very uniform bubble size and spacing for maximum freeze-thaw protection. Cebex 112 entrains less air (typically 1 to 3%) as a secondary benefit to its primary workability function, and the air bubble characteristics are not optimised for freeze-thaw protection. For concrete in exposure conditions where freeze-thaw resistance is required (such as external slabs and pavements in North India exposed to winter freezing), a dedicated AEA combined with Cebex 112 or a superplasticiser provides the best combination of workability and freeze-thaw resistance.