TruCast™ SRA Powder Shrinkage Reducing Admixture

Reduce Drying Shrinkage, Curling, Warping & Cracking in High-Performance Concrete

TruCast™ SRA is a premium powdered shrinkage reducing admixture designed to improve dimensional stability in concrete by reducing the internal stresses created as concrete dries. By lowering capillary tension within the cement matrix, TruCast™ SRA helps minimize drying shrinkage, curling, warping, and shrinkage-related cracking while producing flatter, more accurate castings.

Unlike many liquid shrinkage reducing admixtures, TruCast™ SRA is supplied as a free-flowing powder, making it ideal for dry-blended concrete mixes, bagged mix designs, and manufacturers who want the convenience of adding shrinkage reduction directly into their dry ingredients.

Whether you're producing concrete countertops, GFRC panels, UHPC components, architectural precast, cast stone, or decorative concrete products, TruCast™ SRA helps improve long-term dimensional stability without changing your batching process.

Why Use a Shrinkage Reducing Admixture?

All cement-based materials shrink as they cure and dry. As moisture leaves the concrete, microscopic capillary forces develop inside the hardened cement paste. These internal stresses can cause:

• Drying shrinkage
• Curling
• Warping
• Hairline cracking
• Dimensional changes
• Corner lift
• Surface defects
• Reduced mold accuracy

A shrinkage reducing admixture works by lowering the surface tension of water within the pore structure, reducing these internal stresses before they become visible defects.

The result is flatter, stronger, more dimensionally stable concrete.

Benefits of TruCast™ SRA

• Reduces drying shrinkage
• Minimizes curling and warping
• Helps reduce shrinkage cracking
• Improves dimensional stability
• Helps concrete cast truer to the mold
• Produces flatter castings
• Improves mold fidelity
• Easy to dry blend
• Compatible with most concrete admixtures
• Ideal for both production and custom mix designs

Ideal Applications

TruCast™ SRA is recommended for:

• Concrete countertops
• GFRC (Glass Fiber Reinforced Concrete)
• UHPC
• ECC
• Architectural precast
• Concrete furniture
• Fireplace surrounds
• Cast stone
• Decorative concrete
• Thin concrete panels
• Wall panels
• Concrete sinks
• Dry bag mix manufacturing
• Specialty cementitious products

Why Choose a Powdered Shrinkage Reducing Admixture?

Powdered SRAs offer several advantages over traditional liquid products.

• Easily incorporated into dry-blended mixes
• Simplifies packaging and shipping
• Eliminates liquid measuring during batching
• Excellent for bagged concrete mixes
• Consistent dispersion throughout the mix
• Longer shelf life than many liquid admixtures

A powdered SRA provides excellent process control while maintaining the performance expected from premium shrinkage reducing technology.

Recommended Dosage

Typical Dosage

1.0% of the total dry batch weight

Recommended Range

0.5%–2.0% of the total dry batch weight

Note: Dosage should be calculated using the total weight of all dry ingredients in the mix, including cement, aggregates, pozzolans, fillers, fibers, and other powdered materials.

Trial batches are recommended to determine the optimum dosage for each specific mix design.

Coverage

Coverage is based on the recommended dosage of 1.0% of total dry batch weight.

Compatibility

TruCast™ SRA is compatible with most Portland cement-based systems including:

• Acrylic polymers
• Powdered polymers
• Superplasticizers
• Metakaolin
• Fly ash
• Slag cement
• Glass pozzolans
• Silica fume
• AR Glass fibers
• PVA fibers
• Steel fibers
• Synthetic fibers

Frequently Asked Questions

What does a shrinkage reducing admixture do?

A shrinkage reducing admixture decreases the surface tension of pore water inside concrete. This lowers internal drying stresses that can cause shrinkage, curling, warping, and cracking.

Does a shrinkage reducing admixture increase strength?

Its primary purpose is dimensional stability rather than compressive strength. However, by reducing shrinkage-related cracking, it can improve the long-term durability and appearance of concrete.

Is TruCast™ SRA compatible with GFRC?

Yes. TruCast™ SRA works well in GFRC, UHPC, ECC, cast stone, countertops, and many other high-performance cementitious systems.

Can I use TruCast™ SRA in bagged concrete mixes?

Yes. Because it is supplied as a dry powder, TruCast™ SRA is especially well suited for dry-blended concrete mixes and packaged products.

Will it affect color?

TruCast™ SRA is white to off-white and generally has little to no noticeable effect on concrete color when used at recommended dosages.

Can it be used with acrylic polymers?

Yes. It is compatible with most commonly used acrylic polymers, powdered polymers, superplasticizers, fibers, pozzolans, and other concrete admixtures.

Technical Information

• Appearance: White free-flowing powder
• Typical dosage: Approximately 1% of total dry batch weight
• Dosage range: 0.5–2.0%
• Application: Dry-blended concrete and mortar systems
• Storage: Store in a cool, dry location
• Shelf life: Approximately 12 months when properly stored

Why Buy TruCast™ SRA from Fishstone?

Fishstone Concrete Products has been serving the decorative concrete industry since 2006. We don't simply distribute materials—we develop, test, and support the products we sell.

When you purchase TruCast™ SRA, you also receive access to:

• Technical support
• Mix design assistance
• Product recommendations
• Troubleshooting guidance
• Training resources
• Decorative concrete expertise

Whether you're making one countertop or producing architectural precast at scale, we're here to help you achieve consistent, professional results.