TruCast SiX™ is a multi-component powdered concrete admixture developed to simplify the production of advanced, high-performance concrete. It combines carefully selected performance-enhancing components, including ultrafine reactive materials, plasticizing technology, shrinkage-reducing components, polymer, and air-management additives.
The starting mix designs below provide practical formulations for GFRC, ECC, UHPC-style high-performance concrete, self-consolidating concrete, concrete countertops, sinks, furniture, panels, cladding, tile, and architectural precast.
Choose a TruCast SiX Mix Design
The formulations below are approximately 50 lb batches and have been rounded to practical whole- and half-pound quantities for easier batching.
High-Performance GFRC Mix
A versatile starting formulation for countertops, sinks, furniture, architectural panels, cladding, and other high-performance GFRC applications.
| Portland Cement | 19.5 lb |
| #40–50 Silica Sand | 19.5 lb |
| TruCast SiX | 4 lb |
| Water | 6.5 lb |
| AR Glass Fiber | 1–1.5 lb |
Total Batch Weight: approximately 50 lb
Coverage: approximately 0.4 cu. ft. or 5 sq. ft. at 1 inch thick
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 that are dosed 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) Mix
A starting formulation for thin-section, fiber-reinforced concrete where toughness, crack control, ductility, and workability are important.
| Portland Cement | 19 lb |
| Silica Fume | 1 lb |
| #40–50 Silica Sand | 20 lb |
| TruCast SiX | 4 lb |
| Water | 6.5 lb |
| PVA Fiber | 0.5 lb / 8 oz |
Total Batch Weight: approximately 50 lb
Coverage: approximately 0.4 cu. ft. or 5 sq. ft. at 1 inch thick
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.
UHPC-Style High-Performance Concrete Mix
A starting formulation for dense, low-water, high-performance architectural and specialty precast concrete.
| Portland Cement | 16.5 lb |
| Silica Fume | 1 lb |
| #40–50 Silica Sand | 14 lb |
| #50–80 Silica Sand | 5.5 lb |
| 325-Mesh Silica Flour | 3.5 lb |
| TruCast SiX | 3.5 lb |
| Water | 5.5–5.8 lb |
| PVA-100 Fiber | 0.5 lb / 8 oz |
Total Batch Weight: approximately 50 lb
Coverage: approximately 0.4 cu. ft. or 5 sq. ft. at 1 inch thick
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, the following simple formulation provides an easy starting point.
- 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 28 lb of water with 110 lb total cementitious material:
28 ÷ 110 = approximately 0.25 water-to-cementitious ratio
Actual water demand will vary with cement chemistry, sand moisture, fibers, pigments, temperature, mixing equipment, and other ingredients.
TruCast SiX Dosage
To keep batching simple, calculate TruCast SiX based on the weight of the Portland cement:
Example:
100 lb Portland Cement = approximately 20 lb TruCast SiX
Calculating Total Cementitious Weight
Approximately 50% of TruCast SiX is reactive material that contributes to the cementitious system. Include this portion when calculating pigments or other admixtures dosed based on total cementitious weight.
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
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.
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.
Achieving a Fluid, Self-Consolidating Mix
- 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.
- Use ice as part of the batch water in warm-weather conditions.
- 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.
Adjusting and 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.
- 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.
TruCast SiX Mix Design FAQ
What is the recommended TruCast SiX dosage?
A practical starting dosage is approximately 20% of the Portland cement weight. For example, 100 lb of Portland cement would use approximately 20 lb of TruCast SiX.
Can TruCast SiX be used for GFRC?
Yes. TruCast SiX can be used as the performance-admixture component in high-performance GFRC formulations using AR glass fiber reinforcement.
Can TruCast SiX be used for ECC?
Yes. TruCast SiX can be used as a starting platform for ECC-style mixes incorporating PVA fiber and suitable fine aggregates and pozzolanic materials.
Can TruCast SiX be used to make UHPC?
TruCast SiX can be used as the admixture platform for dense, low-water, high-performance mixes using optimized fine aggregates, reactive materials, and fiber reinforcement. Final performance will depend on the complete mix design, materials, curing, and testing.
What type of sand should I use?
Clean, consistently graded silica sand is recommended. #40–50 silica sand works well for many applications, while blends of different particle sizes may be useful when developing more densely packed high-performance formulations.
How much water should I use?
Use the recommended water amount as a starting point and make small adjustments only as needed. Cement chemistry, sand moisture, pigments, fibers, temperature, and mixer efficiency can all change water demand.
Can I add additional plasticizer?
If additional flow is required, a compatible high-range water reducer or plasticizer may be added in small, controlled increments. Avoid adding unnecessary water solely to increase flow.
How do I calculate pigment dosage?
Calculate pigment dosage from the total cementitious weight, including Portland cement, separately added reactive pozzolans, and approximately 50% of the TruCast SiX weight.
Build Your TruCast SiX Mix
TruCast SiX is designed to simplify advanced concrete mix development while allowing you to select locally available cement, aggregates, pigments, and reinforcement for your application.
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