Pretesting of the concrete mix should be performed before use, 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 Applied Technologies representative for guidance.
Packaging & Handling
Daratard 17 is available in bulk, delivered by metered tank trucks, totes and drums.
Daratard 17 will freeze at about 28 °F (-2 °C), but will return to full strength after thawing and thorough agitation.
Dispensing Equipment
A complete line of accurate, automatic dispensing equipment is available. Daratard 17 may be introduced to the mix with the sand or with the water.
Specifications
Concrete shall be designed in accordance with Standard Recommended Practice for Selecting Proportions for Concrete, ACI 211.1.
The set-retarding/water-reducing admixture shall comply with ASTM Designation C494, Type D admixture, and shall be Daratard 17, as manufactured by GCP Applied Technologies, or equal. Certification of compliance shall be made available on request. It shall be used in strict accordance with the manufacturers’ recommendations.
The addition rate shall be adjusted to produce the specified retardation of the concrete mix at all temperatures.