Slab / Footing / Wall
V = Length × Width × Thickness
Circular Column
V = π × r² × Height
With Waste
Total = V × (1 + Waste%)
Standard / General
Strong / Structural
Medium Strength
Disclaimer
Results are estimates. Actual material requirements may vary due to site conditions, mix design, and aggregate properties. Always consult a structural engineer for critical applications.
Concrete is a composite material composed of cement, water, and aggregates (sand and gravel or crusite stone). When mixed together, these ingredients form a paste that hardens over time through a chemical process called hydration. Concrete is one of the most widely used construction materials in the world due to its strength, durability, and versatility.
The strength of concrete depends on several factors including the water-to-cement ratio, the type and quality of aggregates used, proper mixing and placement techniques, and adequate curing time. Modern concrete can be enhanced with various admixtures to improve workability, set time, strength, and durability.
Mix ratios express the proportion of cement, sand, and aggregate by volume. The ratio 1:2:4 means 1 part cement, 2 parts sand, and 4 parts aggregate. Different ratios produce concrete with varying strengths suitable for different applications.
M15 (1:2:4) - Standard Mix
Suitable for general construction, floor slabs, pathways, and non-structural applications. Achieves approximately 15 MPa compressive strength after 28 days.
M20 (1:1.5:3) - Strong Mix
Used for structural elements like beams, columns, and foundations. Provides approximately 20 MPa compressive strength, making it suitable for load-bearing applications.
Slabs
Flat horizontal surfaces like floors, driveways, and patios. Typically 100-150mm thick for residential applications.
Footings
Foundation elements that transfer building loads to the ground. Size depends on soil conditions and structural loads.
Columns
Vertical structural elements that support beams and slabs. Require higher strength concrete (M20 or above) and reinforcement.
Walls
Retaining walls, basement walls, and boundary walls. Thickness varies based on height and lateral pressure.
- Add waste allowance: Always include 5-10% extra for spillage, uneven surfaces, and over-excavation.
- Measure accurately: Double-check all dimensions before ordering materials to avoid shortages or excess.
- Consider site conditions: Uneven ground, formwork variations, and reinforcement displacement can affect actual volume needed.
- Order slightly more: Running short during a pour is costly; excess concrete can often be used for other small projects.
- Consult professionals: For structural applications, always have designs reviewed by a qualified engineer.