KingAdd 50SC®
Alkali-free powder accelerator for dry-mix sprayed concrete
SpecWorld has the Spec Pack, CSI specification and drawings for registered specifiers.
Overview
KingAdd 50SC is a non-toxic, alkali-free powder accelerator for dry-mix spraying concrete. Varied dosages of KingAdd 50SC will provide the required setting time.
Where to use
Dry-mix sprayed concrete applications such as:
- Initial and permanent support of surfaces in underground spaces.
- Slope and rock stabilization.
- Repair & renovation works.
Why use it
- Alkali-free, chloride-free and non-toxic.
- No ground water contaminations from alkali leachates.
- Improves the bond of shotcrete to the rock or concrete.
- Provides improved overhead spraying.
- Rapid setting for early strength requirements.
Technical properties
| Colour | White powder |
|---|---|
| Bulk density | 800 – 1000 kg/m³ |
| pH | 4 ± 1 (1% solution) |
| Chloride contentBS 5075 | < 0.1% |
Standards and approvals
KingAdd 50SC complies with ASTM C1141/C1141M, Types I, Grade 9, Class B.
COMPATIBILITY
Cement
KingAdd 50SC is recommended to be used in concrete mixes based on Ordinary Portland Cement (OPC) or Rapid Hardening Portland Cement (RHPC). The minimum cement weight per cubic meter of the concrete mix should be no less than 350 kg/m3.
With the assistance of KINGKRETE Technical Service preliminary testing can be conducted for KingAdd 50SC compatibility with cements available to the job site.
Admixtures
KingAdd 50SC is compatible with all KINGKRETE admixtures. It is recommended KINGKRETE Technical Department should be contacted for advice.
Do not use other set accelerators in the concrete mix.
How to use
Method of use
Dosage
Spraying trials should be conducted to determine the optimum dosage of KingAdd 50SC to meet the performance requirements by using the materials and conditions in actual use.
Dosage of KingAdd 50SC will vary depending on the performance requirements of the spraying concrete, cement type, age and content, temperature of the spraying concrete, substrate and air, the water to binder ratio as well as the other admixtures and materials in the concrete mix.
Typical dosage is between 5% - 10% of binder (cement, PFA, GGBFS, microsilica, etc.) content by weight.
EFFECTS OF OVER DOSAGE
Overdosing of KingAdd 50SC will decrease the ultimate concrete strength.
Application
KingAdd 50SC can be added directly to the dry sprayed concrete mix providing that:
- Moisture content of the mix is less the 6%, and
- Minimum cement weight per cubic meter of the concrete mix should be no less than 350 kg/m³.
Cleaning
KingAdd 50SC can be washed with fresh cold water.
Coverage, packaging and storage
Packaging
KingAdd 50SC is available in 15 kg bags.
Storage
Shelf life is 1 year when stored under cover, out of direct sunlight and protected from extremes of temperature.
Failure to comply with the recommended storage conditions may result in premature deterioration of the product or packaging. For specific storage advice consult KingKrete's Technical Services Department.
Health and safety
As with all chemical products, care should be taken during use and storage to avoid contact with eyes, mouth, skin and foodstuffs. Treat splashes to eyes and skin immediately. If accidentally ingested, seek medical attention. Reseal containers after use. Use in well ventilated areas and avoid inhalation.