TruCast SiX High-Performance Concrete Mix Designs
TruCast SiX™ is a multi-component powdered concrete admixture designed to simplify the production of high-performance, self-consolidating concrete. TruCast SiX combines carefully selected performance-enhancing components, including ultrafine reactive materials, plasticizing technology, shrinkage-reducing components, polymer, and air-management additives.
TruCast SiX is designed for use in:
- High-Performance Glass Fiber Reinforced Concrete (GFRC)
- Engineered Cementitious Composites (ECC)
- Ultra-High Performance Concrete (UHPC)
- Self-Consolidating Concrete (SCC)
- Concrete countertops, sinks, furniture, panels, cladding, tile, and architectural precast
The mix designs below are intended as starting formulations. Portland cement, sand gradation, fibers, pigments, temperature, mixing equipment, and locally sourced materials can all affect performance. Testing and minor adjustments may be necessary before moving a formulation into production.
TruCast SiX Dosage
To keep batching simple, calculate TruCast SiX based on the weight of the Portland cement:
Portland Cement × 20% = TruCast SiX
Example:
100 lb Portland Cement = approximately 20 lb TruCast SiX
Approximately 50% of TruCast SiX is reactive material that contributes to the cementitious system and should be included when calculating pigments or other admixtures that are dosed based on total cementitious weight.
Total Cementitious Weight = Portland Cement + Other Cementitious/Pozzolanic Materials + 50% of TruCast SiX
Example:
100 lb Portland Cement
+ 10 lb reactive portion from 20 lb TruCast SiX
= 110 lb Total Cementitious Weight
If pigment is dosed at 3% of cementitious weight:
110 lb × 3% = 3.3 lb pigment
Two Simple Rules
- TruCast SiX dosage: Calculate from Portland cement weight.
- Pigments and cementitious-based admixtures: Calculate from total cementitious weight, including 50% of TruCast SiX.
Achieving a Fluid, Self-Consolidating Mix
For best results:
- Use clean, consistently graded silica sand.
- Rounded or spherical-shaped silica sand generally improves flow.
- #40–50 silica sand works well for many applications.
- Accurately weigh all ingredients.
- Avoid excessive water at the beginning of the mixing cycle.
- Mix until smooth, fluid, and homogeneous.
- Allow the mixture to rest approximately 2–5 minutes, then remix.
- If additional flow is required, make small adjustments with water or a compatible high-range water reducer/plasticizer.
- Avoid excessive water, which can reduce strength and increase shrinkage.
- Make sure casting tables and molds are level when using highly fluid mixes.
- Pour into one location whenever practical and allow the concrete to flow and self-consolidate.
- Cover with plastic after casting to prevent rapid moisture loss during the initial cure.
Actual water demand will vary depending on cement chemistry, sand moisture, pigments, fibers, temperature, and other ingredients.
Mixing TruCast SiX
Option 1 – Dry Blend: Pre-blend TruCast SiX with the Portland cement, sand, pozzolans, and other dry ingredients before introducing the batch water.
Option 2 – Add to Batch Water: Gradually introduce TruCast SiX into the batch water while mixing. Once well dispersed, add the Portland cement, sand, and remaining dry materials.
Either method can produce excellent results. Mixer type, batch size, sequencing, fibers, and other materials may determine which method works best.
Recommended Starting Mix Designs
The following approximately 50 lb formulations have been rounded to practical whole- and half-pound quantities for easier batching. Slight variations from the target ratios are acceptable and may be adjusted during testing.
High-Performance GFRC
A versatile starting formulation for countertops, sinks, furniture, architectural panels, cladding, and other high-performance GFRC applications.
- 19.5 lb Portland Cement
- 19.5 lb #40–50 Silica Sand
- 4 lb TruCast SiX
- 6 lb Water
- 1 lb AR Glass Fiber
Total Batch Weight: approximately 50 lb
Cementitious calculation:
4 lb TruCast SiX × 50% = 2 lb reactive portion
19.5 lb Portland Cement + 2 lb = 21.5 lb Total Cementitious Weight
Use approximately 21.5 lb when calculating pigments or supplemental admixtures based on cementitious weight.
Fiber dosage may be adjusted depending on whether the mixture is being used as a face coat, premix GFRC, backer mix, or structural casting.
Engineered Cementitious Composite (ECC)
A starting formulation for thin-section, fiber-reinforced concrete where toughness, crack control, flexibility, and workability are important.
- 19 lb Portland Cement
- 1 lb Silica Fume
- 20 lb #40–50 Silica Sand
- 4 lb TruCast SiX
- 5.5 lb Water
- 0.5 lb PVA Fiber (8 oz)
Total Batch Weight: approximately 50 lb
Cementitious calculation:
4 lb TruCast SiX × 50% = 2 lb reactive portion
19 lb Portland Cement + 1 lb Silica Fume + 2 lb = 22 lb Total Cementitious Weight
Use approximately 22 lb when calculating pigments or other admixtures based on cementitious weight.
PVA fibers should generally be introduced gradually after the base mixture develops good flow and a uniform consistency.
Ultra-High Performance Concrete (UHPC)
A starting formulation for dense, high-strength architectural and specialty precast concrete.
- 16.5 lb Portland Cement
- 1 lb Silica Fume
- 14 lb #40–50 Silica Sand
- 5.5 lb #50–80 Silica Sand
- 3.5 lb 325-Mesh Silica Flour
- 3.5 lb TruCast SiX
- 5.5 lb Water
- 0.5 lb PVA Fiber (8 oz)
Total Batch Weight: approximately 50 lb
Cementitious calculation:
3.5 lb TruCast SiX × 50% = approximately 1.75 lb reactive portion
16.5 lb Portland Cement + 1 lb Silica Fume + 1.75 lb = approximately 19.25 lb Total Cementitious Weight
Use approximately 19.25 lb when calculating pigments or supplemental admixtures based on cementitious weight.
Depending on the application, PVA fiber may be replaced or supplemented with other suitable reinforcing fibers.
Simple TruCast SiX Starting Formula
For customers developing their own mix design:
- 100 lb Portland Cement
- 100 lb Silica Sand
- 20 lb TruCast SiX
- Start with approximately 28 lb Water
- Add reinforcing fiber as required
The 20 lb of TruCast SiX contributes approximately 10 lb of reactive material to the cementitious calculation:
100 lb Portland Cement + 10 lb reactive portion = 110 lb Total Cementitious Weight
Use 110 lb, rather than 100 lb, when calculating pigments or other admixtures dosed based on total cementitious weight.
Water-to-Cementitious Ratio
Using the simple starting formulation:
100 lb Portland Cement
+ 10 lb reactive portion of TruCast SiX
= 110 lb Total Cementitious Weight
With 28 lb water:
28 ÷ 110 = approximately 0.25 water-to-cementitious ratio
Actual water demand will vary with the cement, sand moisture, fibers, pigments, temperature, mixing equipment, and other ingredients.
Pigments and Additional Admixtures
When adding integral pigment, supplemental plasticizer, shrinkage reducer, or another admixture that is dosed based on cementitious weight, use:
Portland Cement + Other Cementitious/Pozzolanic Materials + 50% of TruCast SiX
Example:
100 lb Portland Cement
+ 10 lb reactive portion from 20 lb TruCast SiX
= 110 lb Total Cementitious Weight
At a 3% pigment dosage:
110 lb × 3% = 3.3 lb pigment
If silica fume, metakaolin, or another reactive pozzolan is added separately, include that material in the total cementitious calculation as well.
Developing Your Mix
There is no single formulation that will perform identically with every combination of raw materials. Begin with one of the recommended formulations and make small, documented adjustments to:
- Water content
- Sand gradation
- Fiber type and dosage
- Supplemental plasticizer
- Pigment dosage
- Additional pozzolan content
- Mixing sequence and mixing time
- Resting and remixing time
- Curing conditions
Once the desired flow, surface quality, strength, dimensional stability, and handling characteristics have been achieved, document the formulation and maintain consistent batching procedures.
Always perform test batches before moving a new formulation into full production.