1. What is M20 Concrete Mix Ratio?

The M20 concrete mix ratio (1:1.5:3) is a standard proportion of cement, sand, and gravel recommended for driveways and other general construction purposes. It provides a compressive strength of approximately 20 MPa after 28 days of curing.

2. How Does the Calculator Work?

The calculator uses the mix ratio to determine quantities:

Where:

• Standard M20 ratio is 1 (cement) : 1.5 (sand) : 3 (gravel)
• Total ratio parts = 1 + 1.5 + 3 = 5.5
• For 1 m³ concrete: Cement = 1/5.5 ≈ 0.18 m³
• Sand = 1.5/5.5 ≈ 0.27 m³
• Gravel = 3/5.5 ≈ 0.55 m³

3. Importance of Proper Mix Ratios

Details: Correct mix ratios ensure the concrete has adequate strength, durability, and workability for its intended use. M20 is ideal for driveways as it balances strength and cost.

4. Using the Calculator

Tips: Enter the desired mix ratio (default is 1:1.5:3 for M20) and the total volume needed. The calculator will determine the exact quantities of each component required.

5. Frequently Asked Questions (FAQ)

Q1: Why is the M20 ratio recommended for driveways?
A: M20 provides sufficient strength (20 MPa) for vehicle loads while being economical and easy to work with.

Q2: Can I adjust the ratio for different strengths?
A: Yes, M15 (1:2:4) for lighter duty or M25 (1:1:2) for heavier loads can be used by changing the ratios.

Q3: How much water should I add?
A: Typically 0.4-0.6 times the cement weight (20-30 liters per 50kg bag), but adjust for desired consistency.

Q4: What if my measurements aren't exact?
A: Small variations are acceptable, but significant deviations will affect concrete quality.

Q5: How many cement bags are needed per m³?
A: Approximately 7.5 bags (375kg) of cement per m³ for M20 mix.