Uses
ZYLA® 625 water reducer is used to produce concrete mixes with lower water content (typically 3% to 10% reduction), greater plasticity and higher compressive strengths. It is suitable for normal weight and light weight concrete in ready-mix, precast and prestressed applications.
Finishability
The unique chemistry of ZYLA® 625 product positively impacts the finishability of concrete by providing a creamier and more homogenous texture, with more uniform and increased bleed rate relative to traditional lignin-based water reducers. The influence of ZYLA® 625 product on the finishability of lean mixes has been particularly noticeable. Floating and troweling, by machine or hand, imparts a smooth, close tolerance surface.
Addition Rates
The addition rate range of 3 to 5 fl oz/100 lbs (195 to 325 mL/100 kg) of cement or cementitious is typical for most applications. However addition rates of 2 to 10 fl oz/100 lbs (130 to 652 mL/100 kg) of cement or cementitious may be used if local testing shows acceptable performance. Pretesting is required to determine the appropriate addition rate for desired performance. The optimum addition rate depends on the other concrete mixture components, job conditions, and desired performance characteristics.
Compatibility with Other Admixtures and Batch Sequencing
ZYLA® 625 water reducer is compatible with most admixtures as long as they are added separately to the concrete mix, usually through the water holding tank discharge line. However, it is not recommended for use in concrete containing naphthalene-based and melamine-based admixtures. In general, it is recommended that ZYLA® 625 admixture be added to the concrete mix near the end of the batch sequence for optimum performance. Different sequencing may be used if local testing shows better performance. Please see GCP Technical Bulletin TB-0110, Admixture Dispenser Discharge Line Location and Sequencing for Concrete Batching Operations for further recommendations. ZYLA® 625 water reducer should not come in contact with any other admixture before or during the batching process, even if diluted in mix water.
Pretesting of the concrete mix should be performed before use, and as conditions and materials change in order to assure compatibility, and to optimize dosage rates, addition times in the batch sequencing and concrete performance. For concrete that requires air entrainment, the use of an ASTM C260 air-entraining agent (such as Daravair® or Darex® product lines) is recommended to provide suitable air void parameters for freeze-thaw resistance.
Please consult your GCP representative for guidance.