Product Description
WRDA® P79 is an aqueous solution of complex organic compounds combined with other chemicals which increase its beneficial effects on the quality and plasticity of a concrete mix. It does not contain calcium chloride. WRDA® P79 is manufactured under rigid control which provides uniform, predictable performance. It is supplied as a dark brown, low viscosity liquid, ready-to-use as received.
WRDA® P79 is a chemical admixture meeting the requirements of the following chemical admixture specifications for concrete: ASTM C 494 as a Type A and Type D; BS 5075: Part 1; GB 8076-1997.
One Litre weighs approximately 1.11kg ± 0.02kg.
Applications
WRDA® P79 makes a workable mix with up to 15% less water and yields a stronger, less permeable and more durable concrete. It is used in ready mix plants, job site plants and concrete pavers, for normal weight and light weight concrete, in block, precast and prestressed concrete plants. It should be noted that WRDA® P79 is particularly effective in concrete containing slag or fly ash (pozzolans).
Compared to other water reducers WRDA® P79 will typically impart the following additional benefits:
- Higher early compressive and flexural strengths
- Improved concrete finish
Chemical Action
As a dispersing agent, WRDA® P79 lessens the natural interparticle attraction between cement grains in water. It does this by colloidal action, by absorption on the cement particles thus reducing their tendency to clump together and makes the mix more workable with less water. As a cement catalyst, WRDA® P79 effects a more complete hydration of the cement, begining immediately after the cement and water come together at the lower additions of WRDA® P79 or immediately after a period of designed and controlled hydration at the higher additions. WRDA® P79 increases the gel content of the concrete, the paste or binder that “glues” the concrete aggregates together. The increased gel content adds to the water retention and internal cohesiveness of the mix, reducing bleeding and segregation as it increases workability and placeability.
Dispensing Equipment
Please contact your local GCP representative for further information regarding the dispensing equipment for this product.
Addition Rates
WRDA® P79 will provide water reduction with no retardation. At higher dosage rates, it will provide some retardation. However, after the period of initial retardation hydration continues rapidly and completely. The amount of WRDA® P79 to be used will typically range from 200 to 600mL / 100kg of cementitious material depending upon job requirements (for dosage rates above 600mL / 100kg cementitious material, please consult your local GCP representative).
Compatibility with Other Admixtures
WRDA® P79 is compatible with all air-entraining mixtures. Due to a synergistic effect of WRDA® P79, the quantity of air-entraining agent added to WRDA® P79 admixtured concrete may be reduced by 25-50%. By combining the separate effects of air entrainment and dispersion, the water requirement of concrete may be reduced up to 20%. Each admixture should be added separately. WRDA® P79 contains no calcium chloride but is compatible in concrete with calcium chloride. Again each admixture should be added separately
Packaging
WRDA® P79 is available in bulk, and 205L drums. WRDA® P79 contains no flammable ingredients. It will freeze at about -2ºC but will return to full strength after thawing and thorough mechanical agitation.
Health and Safety
See WRDA® P79 Material Safety Data Sheet or consult GCP Applied Technologies.