Project Requirements
Project:
Dimensions:
Wastage Allowance:
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Environmental Impact Comparison
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0 kg COâ‚‚
0% reduction vs GP cement
Prescribed Mix Guide for Dunlop Envirocem
Setting Times
Initial Set: 130-160 minutes (approximately 2-2.5 hours)
Final Set: 3.5-4 hours
Note: Weather conditions and ambient temperature can significantly impact setting times. Cold weather may extend setting times, while hot weather may accelerate them. Plan accordingly and avoid working in extreme conditions.
Critical: Aggregate Moisture Content
Why It Matters: Aggregate moisture dramatically affects your water-to-cement ratio and final concrete strength. Wet aggregate contains absorbed water that contributes to the total mix water, potentially weakening your concrete if not accounted for.
Visual Assessment: Dry aggregate flows freely and appears dusty. Damp aggregate feels cool and slightly moist. Wet aggregate appears shiny, clumps together, and may have visible surface water.
Best Practice: Use aggregate stored under cover when possible. If using wet aggregate (common after rain or from outdoor stockpiles), reduce your added water accordingly. Start with 75% of the calculated water amount, mix thoroughly, then add water gradually until achieving proper workability. It's easier to add water than to fix an over-wet mix.
Professional Tip: For critical structural work, consider the "squeeze test" - grab a handful of your mixed aggregate. If water drips out when squeezed, significantly reduce added water. If it holds shape when squeezed but crumbles easily, moisture content is moderate - reduce water by 20-30%. If it falls apart immediately, it's relatively dry and safe to use calculated water amounts.
Important Information
General Disclaimer: This calculator provides estimates only. Actual requirements may vary based on site conditions, application method, and material wastage. Always consult product specifications and professional advice for critical applications.
Mixing Best Practices: Use clean, potable water and quality aggregate (combined sand and gravel, or premixed concrete aggregate). Add dry materials to mixer first, then gradually add water while mixing. Mix for at least 2-3 minutes until you achieve a uniform, workable consistency. The mix should be smooth and cohesive - not too wet (sloppy) or too dry (crumbly). Proper consistency will hold its shape when formed but flow smoothly when worked. Avoid over-watering as this significantly reduces final strength. Begin your project immediately after mixing - do not let mixed concrete sit for extended periods.
Curing Best Practices: Proper curing is critical for achieving full strength. Keep concrete continuously moist for at least 7 days after placement. Spray with water regularly (especially in warm or windy conditions) or apply a quality curing compound. Protect from direct sunlight, wind, and rain during the curing period. Cover during cold weather (below 10°C). Allow 24 hours before foot traffic and minimum 7 days before vehicle traffic. Full strength develops over 28 days.
Safety Reminder: Always wear appropriate Personal Protective Equipment (PPE) when working with cement products. This includes safety glasses, dust mask or respirator, waterproof gloves, and protective clothing. Avoid skin contact and inhalation of dust. Wash skin immediately if contact occurs. Keep away from children. Store in a dry place. Read product labels and safety data sheets before use.