Concrete Mix Calculator
Interactive Concrete Mix Calculator
ENGINEERING SCHEMATIC
Site Batching Ratios: Cement : Sand : Gravel Cement Bags Required (94 lb Portland)
6.9 bags
(651 lbs Portland cement) Sand (Fine Aggregate)
0.69 tons
1,386 lbs Gravel (Coarse Aggregate)
1.09 tons
2,183 lbs Clean Mixing Water
39.1 gal
148 liters (w/c ratio 0.5) Estimated Design Strength
3000 PSI
28-day standard moist cure Standard Concrete Mix Ratios & Compressive Strengths
Concrete mix proportions are expressed as Cement : Sand : Coarse Aggregate (Gravel) by volume. Adding water initiates hydration of the Portland cement, binding the aggregates into solid artificial stone.
| Mix Ratio | Estimated 28-Day Strength | Water-Cement Ratio (w/c) | Recommended Applications |
|---|---|---|---|
| 1 : 1.5 : 3 | 4,000 PSI | 0.45 | Suspended slabs, structural beams, heavy vehicle driveways |
| 1 : 2 : 3 | 3,000 PSI | 0.50 | Standard residential slabs, patios, footings, sidewalks |
| 1 : 2 : 4 | 2,500 PSI | 0.55 | General unreinforced foundations, non-structural pathways |
| 1 : 3 : 5 | 2,000 PSI | 0.60 | Mass concrete, thrust blocks, trench backfill |
The 1.54 Dry Volume Rule (Why Concrete Shrinks When Mixed)
When dry sand, dry gravel, and dry cement are mixed together with water, fine cement particles and sand grains fill the void spaces between coarse gravel stones. As a result, 1.54 cubic feet of loose dry materials produces only 1.0 cubic foot of consolidated wet concrete.
To produce 1 cubic yard (27 cu ft) of poured concrete, you must batch 27 × 1.54 = 41.58 cubic feet of dry ingredients.