# Concrete Mix Ratio: Getting it Right Every Time

A concrete mix ratio refers to the combination of ingredients that blend together to produce concrete. The concrete mix ratio is a vital factor in determining the strength, durability, and workability of the concrete mixture. The common components of concrete mixture ratios are cement and fine or coarse aggregates like sand and/or gravel. The ratios will change depending on the application for which the concrete is being applied.

It is important to note that concrete mix ratios do not include the amount of water that is needed to hydrate the concrete mixture. Builders typically calculate the water amount separately depending on the specific project requirements.

## Concrete Mix Ratio Types

Concrete mix ratios will vary according to the type of application but also depending on which standard is being applied. Common standards that are used for concrete mixes include nominal concrete mix ratios, standard concrete mix ratios, and designed mix ratios of concrete.

For a homeowner who uses concrete for small home projects, the nominal mix ratio is sufficient. This typically has a higher rate of strength than what someone may require for a small project. Yet, the nominal ratio results in a mixture that is over-rich and not specific enough for large tasks. For these, a builder would use the designed mix ratio that is specified by concrete companies. This ensures that the mix is accurate for the specific type of concrete and project that they are using it to create.

## Nominal Concrete Mix Ratios

Nominal concrete mix ratios refer to the approximate proportion of concrete ingredients without regard to moisture content, specific gravity, and the characteristics of individual materials.

The nominal concrete mix ratio is a good starting point for small home projects because this mix guarantees sufficient concrete strength. But this ratio will not always meet specific job requirements or achieve desired properties. This concrete mix is expressed in volume.

### Nominal Mix 1:1:2

• Cement: Sand: Coarse Aggregates = 1 part, 1 part, 2 parts by volume
• Use this mixture for low-strength applications such as non-structural elements such as walking paths or floor toppings.

### Nominal Mix 1:2:4

• Cement: Sand: Coarse Aggregates = 1 part, 2 parts, 4 parts by volume
• Use this concrete mixture for general construction purposes such as foundations, footings, and walls.

Nominal Mix 1:3:6

• Cement: Sand: Coarse Aggregates = 1 part, 3 parts, 6 parts by volume
• Use this concrete mixture for projects that require concrete with medium strength, such as beams, columns, and slabs.

### Standard Concrete Mix Ratios

Standard concrete mix ratios, like nominal mix ratios, are straightforward. Unlike nominal mixes that just guarantee sufficient strength, standard concrete mix ratios add an extra measure of strength. Industry expertise, research, and testing have helped to shape standard ratios, so these are a good starting place for building professionals. Yet, these standard mix ratios do not account for specific environmental factors and specific project requirements.

### Standard Mix Ratio for General Concrete

• 1:2:3, Cement, Sand, and Coarse Aggregates = 1 part, 2 parts, 3 parts by volume
• Builders use this mix ratio for general construction projects including nonstructural applications like foundations, slabs, columns, and common construction elements.

### Standard Mix Ratio for Reinforced Concrete

• 1:1.5:3, Cement, Sand, and Coarse Aggregates = 1 part, 1.5 parts, 3 parts by volume
• This is the standard mixture that builders use when they want to ensure the concrete has sufficient strength to resist applied loads and provide durability over time.

### Standard Mix Ratio for High-Strength Concrete

• 1:0.7:1.4, Cement, Sand, and Coarse Aggregates = 1 part, 0.7 parts, 1.4 parts by volume
• This is a standard concrete mixture for builders who need concrete that can stand up to heavy loads or extreme conditions.

### Standard Mix Ratio for Lean Concrete

• 1:3:6, Cement, Sand, and Coarse Aggregates = 1 part, 3 parts, 6 parts by volume
• Builders use lean concrete in places where strength is not a factor such as leveling an area or filling a void.

### Designed Concrete Mix Ratios

Designed concrete mix ratios, unlike nominal or standard mix ratios, involve a more customized approach to concrete types. Designed concrete mix ratios are specifically tailored by the concrete manufacturers to meet the unique requirements of a specific concrete type. The customization is based on extensive laboratory testing and calculations to optimize the specific concrete mixture. This mix ratio is common for concrete grades M30-M70.

## Concrete Mix Ratio Charts

This section includes charts for each type of general concrete: nominal/normal, standard, and high-strength concrete.

### Nominal/Normal Concrete Mix Ratios

Concrete GradeMix RatioCompressive Strength - MPa/psi
M51:5:105 MPa/ 725 psi
M7.51:4:87.5 MPa/ 1087 psi
M101:3:610 MPa/ 1450 psi
M151:2:415 MPa/ 2175 psi
M201:1.5:320 MPa/ 2900 psi

### Standard Concrete Mix Ratios

Concrete GradeMix RatioCompressive Strength - MPa/psi
M251:1:225 MPa/ 3625 psi
M30Design Mix30 MPa/ 4350 psi
M35Design Mix35 MPa/ 5075 psi
M40Design Mix40 MPa/ 5800 psi
M45Design Mix45 MPa/ 6525 psi

### High-Strength Concrete Mix Ratios

Concrete GradeMix RatioCompressive Strength - MPa/psi
M50Design Mix50 MPa/ 7250 psi
M55Design Mix55 MPa/ 7975 psi
M60Design Mix60 MPa/ 8700 psi
M65Design Mix65 MPa/ 9425 psi
M70Design Mix70 MPa/ 10150 psi