Description

SikaPlast® PH 8399 – High Performance Water-Reducing & Waterproofing Concrete Admixture

SikaPlast® PH 8399 is a high-performance concrete and mortar admixture based on modified Poly-Carboxylate Ether (PCE) technology. It is developed for demanding Ready-Mix and site-batched concrete applications where high workability, significant water reduction, durability, strength development, and improved concrete performance are required.

The advanced PCE-based formulation provides excellent dispersion of cementitious materials while maintaining workability for extended periods. It is particularly suitable for high-performance concrete, pumped concrete, long-distance transportation, and concrete mixes containing supplementary cementitious materials such as microsilica, GGBFS, and PFA.

What is SikaPlast® PH 8399?

SikaPlast® PH 8399 is a ready-to-use liquid concrete admixture designed to improve the performance and workability of concrete while reducing the amount of mixing water required to achieve a desired consistency.

Its modified poly-carboxylate ether technology enables effective dispersion of cement particles, allowing concrete producers to achieve high workability with reduced water content. This can contribute to improved concrete strength and durability when the concrete mix is properly designed, placed, compacted, and cured.

Sika Bangladesh describes PH 8399 as a high-performance, water-reducing and waterproofing concrete/mortar admixture for demanding concrete applications.

Key Features and Benefits

High Water Reduction

One of the major advantages of SikaPlast® PH 8399 is its ability to reduce the water requirement of concrete while maintaining the desired workability. It is intended for mixes requiring more than 20% water reduction, subject to mix design and trial results.

Excellent Workability Retention

PH 8399 helps concrete retain workability for longer periods. This is particularly beneficial when concrete needs to be transported over longer distances or when site conditions require extended placing time.

Improved Cement Dispersion

The PCE-based formulation provides good dispersion even in concrete mixes containing high levels of cementitious fines. This helps produce a more workable and cohesive concrete mix.

High Workability Without Excessive Segregation

The admixture is designed to provide high workability while helping maintain resistance to segregation and bleeding when the mix is properly proportioned and controlled.

Reduced Pumping Pressure

Its improved flow characteristics can help reduce pumping pressure in suitable concrete mixes, supporting more efficient placement of pumped concrete.

Higher Ultimate Strength

By enabling water reduction while maintaining workability, PH 8399 can contribute to higher ultimate concrete strength when the overall mix design, compaction, and curing are properly controlled.

Easier Finishing

The improved workability of the concrete can make placing and finishing operations easier for construction teams.

Main Applications

SikaPlast® PH 8399 is suitable for a broad range of concrete applications, including:

• Ready-Mix Concrete
• Site-batched concrete
• Pumped concrete
• High-performance concrete
• Durable concrete structures
• Long-distance concrete transportation
• High-workability concrete
• Concrete requiring significant water reduction
• Concrete containing microsilica
• GGBFS-containing concrete
• PFA and high-volume fly ash concrete
• Structural concrete
• Infrastructure projects
• High-rise construction
• Commercial and industrial construction

The exact suitability should be determined through appropriate mix trials and project-specific technical requirements.

Suitable for Ready-Mix Concrete

Ready-Mix concrete often needs to maintain its workability during transportation from the batching plant to the construction site. PH 8399 can be particularly useful in such applications because it provides workability retention while supporting reduced water content.

This makes it a suitable option for concrete suppliers and Ready-Mix plants looking to develop high-performance concrete mixes with controlled workability and strength.

Suitable for Pumped Concrete

Pumping concrete requires appropriate flow characteristics and resistance to segregation. SikaPlast® PH 8399 can help improve the workability and pumpability of properly designed concrete mixes while potentially reducing pumping pressure.

It is therefore useful for applications involving high-rise buildings, deep foundations, bridges, large slabs, columns, beams, and other projects where concrete must be transported through pumping systems.

Use with Supplementary Cementitious Materials

PH 8399 can be used in concrete containing supplementary cementitious materials such as microsilica, GGBFS, and PFA, including high-volume fly ash concrete. These materials can significantly influence concrete rheology and workability, making appropriate admixture selection important.

Application and Dispensing

SikaPlast® PH 8399 is supplied as a ready-to-use liquid. According to the Sika Bangladesh Product Data Sheet, the admixture is dispensed into concrete together with the mixing water.

For enhanced plasticizing and water-reduction effects, Sika recommends adding the admixture to damp concrete after approximately 50–70% of the mixing water has been added.

Adding PH 8399 directly to dry aggregate or cement is not recommended. Thorough mixing is essential, and Sika specifies a minimum mixing cycle of approximately 60 seconds after admixture addition for forced-action mixers.

Recommended Dosage

The optimum dosage should be determined through concrete trial mixes because actual requirements depend on cement type, cementitious material content, aggregate characteristics, water-cementitious ratio, required workability, temperature, transportation time, and project conditions.

As a general guide, Sika Bangladesh recommends approximately 200–1500 ml per 100 kg of cementitious material. Dosages outside this range may be required for specific applications, but these should be established through appropriate trials and technical consultation.

Important Precautions

Correct dosage is essential. Severe overdosing may result in delayed initial and final setting as well as bleeding or segregation.

A slight overdose may not necessarily reduce ultimate strength under suitable conditions, but the effect on concrete workability, formwork pressure, setting time, and stripping time should be properly evaluated.

Therefore, concrete trial mixes should always be conducted before large-scale application.

Technical Properties

According to the Sika Bangladesh Product Data Sheet:

• Composition: Modified Poly-Carboxylate Ether (PCE)
• Appearance: Light brown liquid
• Density: Approximately 1.03 kg/L at 25°C
• pH: ≥ 6
• Total chloride ion content: Nil
• Shelf life: 12 months when properly stored in original unopened packaging
• Storage temperature: +10°C to +40°C
• Packaging: 20 kg, 230 kg, 1000 kg, or bulk on request

The product is also stated by Sika Bangladesh to comply with ASTM C494 Types B, D & G, EN 934-2 T3.1/3.2, IS 9103 and IS 2645.

Compatibility

SikaPlast® PH 8399 is compatible with all types of cement and cementitious materials according to Sika’s product information. It may also be combined with various other Sika products, but Sika recommends conducting trials before combining products in a specific concrete mix.

Storage

Store PH 8399 in dry conditions at temperatures between +10°C and +40°C. Protect the product from direct sunlight and frost. Keep the material in its original, unopened packaging until required for use.

Conclusion

SikaPlast® PH 8399 is a modern PCE-based high-performance concrete admixture designed to improve workability, reduce water demand, support strength development, and enhance the performance of demanding concrete mixes.

Its combination of water reduction, workability retention, high dispersion, pumping performance, and resistance to segregation makes it a valuable solution for Ready-Mix concrete, site-batched concrete, pumped concrete, high-performance structures, and projects using supplementary cementitious materials.

For professional construction projects, the optimum dosage and performance should always be established through suitable trial mixes and in accordance with the latest Sika Product Data Sheet and project-specific requirements.