CASTECHFS50
Micro Silica Slurry 50% – Concrete Additive
CASTECH FS50 is a technically advanced concrete additive composed of finely ground silica fume particles (SiO₂ 92 – 94%) suspended in water with additives for better performance and stability.
Overview
About
CASTECH FS50 is a technically advanced concrete additive composed of finely ground silica fume particles (SiO₂ 92 – 94%) suspended in water with additives for better performance and stability. The slurry has about 50% solid content by weight and enhances concrete performance through optimized reaction with Ca(OH)₂ during hydration. As a supplementary cementitious material, CASTECH FS50 improves the strength, durability and chemical resistance of concrete and reduces its permeability. Its formulation mixes uniformly, improving workability and reducing labour, and it does not form dust, protecting site personnel. It keeps its stability over time without sedimentation or layer separation.
Typical uses
- High-performance concrete – strength, durability and
Compatibility
CASTECH FS50 is generally compatible with most cement-based materials and can be used in combination with other mineral admixtures. Small-scale trials are recommended before use in larger applications.
Benefits
Advantages
Key advantages
- Improved compressive and flexural strength for high-stress applications
- Increased durability: resistance to chemical attack, abrasion and weathering
- Reduced | permeability, | reducing | water penetration and corrosion
- Better workability than silica fume powder – no agglomeration or clumping
- Higher | density, | improving | freeze-thaw resistance and long-term durability
- Environmental benefits – uses an industrial by-product
- Cost-effective over the life of the structure, with reduced repairs, labour and time
Technical data
| Consistence | Homogeneous Liquid |
|---|---|
| Colour | Dark Grey |
| Chloride According to EN 934-2 | < 0.01 (w/w) |
| Solid Content | 50 ± 2.5 % (w/w) |
| Specific Gravity | 1.39 ± 0.03 @ 25°C |
| SiO₂ Content | > 92% (w/w) |
| pH (ISO 4316) | 5.5 ± 1 |
| Equivalent Sodium Oxide | 0.16% w/w |
| Pozzolanic Activity Index | > 107% |
| Specific Surface Area | 15,000 – 25,000 m²/kg |
Typical values. Refer to the TDS for full details and test conditions.
Application
Dosage
Typically 5 – 20% of the total binder content, or replace an equal amount of micro silica powder. For concrete Grade 70 or below, reduce the mix water by 50% of the CASTECH FS50 quantity; above Grade 70, reduce it by 70%. Contact CASTECH for specific advice.
Application
For best results, use a minimum cement content of 350 kg/m³ and a water/cement ratio not exceeding 0.45. An increased dosage of CASTECH superplasticizer may be added where required, subject to trials. The water in the slurry must be included in the calculated water/cement ratio. Add CASTECH FS50 to the mixing water and ensure there has been no settling during storage. For mixing time, the definitions and regulations of EN 206-1 apply.
Packaging & storage
Packaging
CASTECH FS50 is available in 25 L, 50 L, 200 L drums and 1000 L IBC.
Storage & shelf life
Store CASTECH FS50 in closed containers to prevent contamination, stir or agitate regularly and protect from frost. Shelf life is six months from the production date.
Health & safety
Health & Safety
CASTECH FS50 is non-toxic. Any splashes to the skin should be washed immediately with water. Splashes to the eyes should be washed immediately with water and medical advice should be sought.
