CASTECHSP-422
High-range Water-reducing and Accelerating Admixture
CASTECH SP-422 is a high-performance polynaphthalene sulfonate (PNS) based superplasticizer, specially formulated for precast and ready-mix concrete applications requiring high early strength, superior workability, and excellent water reduction.
Overview
About
CASTECH SP-422 is a high-performance polynaphthalene sulfonate (PNS) based superplasticizer, specially formulated for precast and ready-mix concrete applications requiring high early strength, superior workability, and excellent water reduction. Developed using advanced sulfonated polymer technology, CASTECH SP-422 provides powerful cement particle dispersion through electrostatic repulsion, resulting in significant water reduction, improved flow, enhanced early and ultimate strength, and superior concrete surface finish. Its optimized formulation promotes rapid early strength gain, allowing faster demoulding cycles, reduced curing time, and accelerated production, making it ideal for precast concrete plants, prestressed elements, hollow-core slabs, beams, columns, pipes, pavers, and fast-track construction projects.
Typical uses
The excellent dispersion properties of CASTECH SP-422 make it the ideal admixture for precast and ready mixed concrete where low water cement ratios are required. This property allows the production of very high early and high ultimate strength concrete with minimal voids and therefore optimum density. Due to the strength development characteristics, the elimination or reduction of steam curing in precast works be considered as an economical option.
Compatibility
CASTECH SP-422 is compatible with all Portland cements that meet recognized international standards. CASTECH SP-422 must not be used in conjunction with any other admixture unless prior approval is received from CASTECH Technical
Department. CASTECH SP-422is suitable for mixes containing
Micro silica Pulverized fuel ash Ground granulated blast furnace slag cement.
Benefits
Benefits
High water reduction efficiency
Accelerated early strength development
Reduced setting time
Improved workability and flow
Enhanced surface finish
Faster formwork removal
- Increased production efficiency for precast plants
- Improved durability and density of concrete
- Compatible with most cement types and supplementary cementitious materials (SCMs)
The contractor / applicator
- Easier placing and faster strength development
- Improved concrete surfaces
The engineer
- Assurance that concrete meets original specification
- High quality durable concrete
Advantages
During mixing and placement
- High workability without segregation or bleeding
- Can be placed and compacted in congested reinforcement
- Reduced labor requirement
- Improved surface finish
- Chloride free
Effect on hardened concrete properties
- Increased early and ultimate compressive strengths
- Increased flexural strength
- Higher E modulus
- Improved adhesion to reinforcing and stressing steel
- Better resistance to carbonation
- Lower permeability
- Better resistance to aggressive atmospheric conditions
- Reduced shrinkage and creep
Increased durability
Technical data
| Consistence | Liquid |
|---|---|
| Colour | Brown |
| Chloride According to EN 934-2 | Nil |
| Classification According to | Type E and |
| ASTM C494 and ASTM C1017 | Type F |
| Specific Gravity | 1.2±0.03@ 25 0 C |
| Air Entrainment | Less than 1.9% |
| pH (ISO 4316) | 7.0 – 9.0 |
| Alkali Content (EN 480-12) (%) | < 3 |
Typical values. Refer to the TDS for full details and test conditions.
Application
Dosage
The normal dosage for CASTECH SP-422 is between 0.5% and 2.0% per 100 kg of cement (cementitious material). Dosages outside this range are permissible subject to trial mixes.
Application
HPS-002 is a ready to use admixture that is added to the concrete at the time of batching. The maximum effect is achieved when the CASTECH SP-422 is added after the addition of 70% to 80% of the water. CASTECH SP-422 must not be added to the dry materials. Thorough mixing is essential and a minimum mixing cycle, after the addition of the CASTECH SP-422, of 90 seconds for forced action mixers is recommended.
Curing
As with all structural concrete, normal curing methods apply.
Packaging & storage
Packaging
CASTECH SP-422is available in IBC, 210-liter drums and in bulk tanks upon request.
Storage & shelf life
CASTECH SP-422 should be protected from extreme temperature. Should the material become frozen, it must be completely thawed and thoroughly mixed before use. CASTECH SP-422 has a minimum shelf life of 6 months provided temperature is kept within range 5 o C to 30 0 C.
Health & safety
Health & Safety
CASTECH SP-422 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.
