Concrete is a fundamental building material used in various construction projects due to its strength, durability, and versatility. However, not all concrete is created equal, and the type and grade of concrete used plays a crucial role in the strength and quality of a structure. In the United Kingdom, the British Standard (BS) is the widely accepted standard for classifying concrete types and their corresponding ratios. In this article, we will delve into the various types of concrete grades and their corresponding ratios as per the British Standard, providing valuable insights for construction professionals and enthusiasts alike.

## Types of concrete grade and their ratio as per British Standard (BS)

Concrete is a widely used construction material for various structures, including buildings, roads, bridges, and dams. It is a composite material made up of cement, water, aggregates (such as sand and gravel), and sometimes admixtures. The strength, durability, and other properties of concrete depend on its composition, with the most critical factor being the concrete grade.

The British Standard (BS) is a set of specifications and guidelines for concrete used in construction projects in the UK. It categorizes concrete into different grades based on its compressive strength, which is the maximum amount of force a concrete sample can withstand before breaking. The following are the different types of concrete grades and their ratio as per BS.

1. C10 (Gen 1)

C10 grade concrete, also known as Gen 1 concrete, has the lowest strength and is often used for non-structural and decorative purposes, such as in garden paths or floors. The ratio of C10 concrete is 1 part cement, 2 parts fine aggregates (such as sand), and 4 parts coarse aggregates (such as gravel), with a water-cement ratio of 0.6-0.7.

2. C15 (Gen 2)

C15 grade concrete, also known as Gen 2 concrete, has higher strength than C10 and is suitable for structural purposes such as support beams and other light-duty applications. The ratio of C15 concrete is 1 part cement, 2.5 parts fine aggregates, and 5 parts coarse aggregates, with a water-cement ratio of 0.6-0.7.

3. C20 (Gen 3)

C20 grade concrete, also known as Gen 3 concrete, has a higher strength than C15 and is commonly used for structural applications in residential and commercial buildings. The ratio of C20 concrete is 1 part cement, 1.5 parts fine aggregates, and 3 parts coarse aggregates, with a water-cement ratio of 0.55-0.6.

4. C25 (Gen 4)

C25 grade concrete, also known as Gen 4 concrete, has a higher strength than C20 and is often used in construction projects that require a higher load-bearing capacity, such as in foundations and retaining walls. The ratio of C25 concrete is 1 part cement, 1 part fine aggregates, and 2 parts coarse aggregates, with a water-cement ratio of 0.5-0.55.

5. C30 (Gen 5)

C30 grade concrete, also known as Gen 5 concrete, has a higher strength than C25 and is used in heavy-duty construction projects, such as in bridges and high-rise buildings. The ratio of C30 concrete is 1 part cement, 0.7 parts fine aggregates, and 1.5 parts coarse aggregates, with a water-cement ratio of 0.45-0.5.

6. C35 (Gen 6)

C35 grade concrete, also known as Gen 6 concrete, has a higher strength than C30 and is suitable for construction projects that require very high strength, such as in road pavements and industrial floors. The ratio of C35 concrete is 1 part cement, 0.6 parts fine aggregates, and 1.2 parts coarse aggregates, with a water-cement ratio of 0.4-0.45.

7. C40 (Gen 7)

C40

## What are the grades of concrete

Concrete is a widely used construction material that is essential in the field of civil engineering. It is made up of cement, water, aggregates (such as sand, gravel, or crushed stone), and admixtures, and can be poured into different forms and shapes, making it a versatile and useful building material.

The strength and durability of concrete depend on its composition, which is determined by the proportions of its ingredients and the quality of the mixture. These proportions are measured in grades, which represent the compressive strength of concrete at 28 days of curing. The grades of concrete are crucial in determining the performance of the concrete in various construction projects. The most commonly used grades of concrete are:

1. M5 grade concrete: This is the weakest grade of concrete and has a compressive strength of 5 megapascals (MPa) after 28 days of curing. It is primarily used for non-structural purposes such as leveling and filling.

2. M7.5 grade concrete: This grade has a compressive strength of 7.5 MPa at 28 days of curing and is used for minor construction works such as pavement, patio, or footpaths.

3. M10 grade concrete: The M10 grade has a compressive strength of 10 MPa and is commonly used in small residential projects and general construction works.

4. M15 grade concrete: This grade has a compressive strength of 15 MPa and is suitable for construction projects with light to moderate loads such as beams and lintels.

5. M20 grade concrete: The M20 grade has a compressive strength of 20 MPa and is commonly used in the construction of reinforced concrete beam, slabs, columns, and footing.

6. M25 grade concrete: This grade has a compressive strength of 25 MPa and is commonly used in the construction of high-rise buildings, bridges, and heavy-duty pavements.

7. M30 grade concrete: The M30 grade has a compressive strength of 30 MPa and is typically used in the construction of bridges, flyovers, and heavy-duty industrial floors.

8. M35 grade concrete: This grade has a compressive strength of 35 MPa and is suitable for constructing durable and strong structures such as high-rise buildings, heavy-duty industrial floors, and beams.

9. M40 grade concrete: The M40 grade has a compressive strength of 40 MPa and is used in the construction of heavy-duty foundations, large industrial floors, and large-scale infrastructure projects.

10. M45 grade concrete: This grade has a compressive strength of 45 MPa and is used in the construction of critical structures such as dams, retaining walls, and underground structures.

11. M50 grade concrete: The M50 grade has a compressive strength of 50 MPa and is suitable for constructing critical structures with high design loads such as nuclear power plants, high-rise buildings, and long-span bridges.

In conclusion, the selection of the appropriate grade of concrete is vital for ensuring the safety and durability of any structure. A civil engineer will carefully consider the intended use and design specifications to determine the appropriate grade of concrete for a particular construction project. Properly choosing the right grade of concrete will result in a well-constructed and long-lasting structure.

## How many types of concrete grade are there

Concrete is a popular construction material that is used for building various structures such as buildings, bridges, and roads. It is composed of cement, aggregates (such as sand and gravel), water, and admixtures. The quality of concrete is determined by its strength, which is known as its grade. There are several types of concrete grade that are used in construction projects, each with its own specific characteristics and uses.

1. Normal Concrete

Normal concrete is the most commonly used type of concrete and is also known as traditional or regular concrete. It is made from a mixture of cement, aggregates, and water in the ratio of 1:2:4 or 1:3:6. Normal concrete has a compressive strength of 20-40 MPa (megapascals), which makes it suitable for general construction purposes such as building walls, floors, and foundations.

2. High-Strength Concrete

High-strength concrete is a type of concrete that has a compressive strength greater than 40 MPa. It is made by reducing the amount of water in the mixture and using a high cement content or adding admixtures. The use of high-strength concrete is beneficial in constructing tall structures, heavy-duty pavements, and precast elements.

3. Ultra-High-Strength Concrete

Ultra-high-strength concrete (UHPC) is a special type of concrete that has a compressive strength of 150 MPa or more. It is produced by using a very low water-cement ratio, fine aggregates, and high-quality cement. UHPC is commonly used in the construction of bridges, high-rise buildings, and other critical infrastructure.

4. Ready-Mix or Pre-Mixed Concrete

Ready-mix concrete is a type of concrete that is manufactured in a batch plant according to a set recipe and then delivered to the construction site in a ready-to-use form. It is a convenient and efficient option as it eliminates the need for on-site mixing and reduces construction time and labor costs.

5. Reinforced Concrete

Reinforced concrete is a combination of concrete and steel reinforcement bars (rebars) that work together to resist tension and compression forces. It is used in the construction of pillars, beams, and slabs to provide additional strength and durability. The grade of reinforced concrete depends on the strength of the steel bars used.

6. Prestressed Concrete

Prestressed concrete is a type of concrete that has been compressed during its production to make it stronger and more resistant to tension. This is achieved by placing steel tendons inside the concrete before it sets. Prestressed concrete is commonly used in the construction of bridges, parking garages, and high-rise buildings.

7. Self-Compacting Concrete

Self-compacting concrete (SCC) is a type of concrete that is highly flowable and requires no vibration during placement. It is made using a high amount of fine aggregates, mineral admixtures, and superplasticizers. SCC is commonly used in congested areas and for casting complex shapes, such as in architectural and precast concrete elements.

In conclusion, there are various types of concrete grade that are used in construction based on their strength and specific properties. It is important for civil engineers and construction professionals to choose the right type of concrete grade for each project to ensure its success and durability.

## Types of concrete grade and their ratio

In civil engineering, concrete is the most commonly used material in construction due to its strength, durability, and versatility. Concrete is a composite material composed of cement, water, aggregates (such as sand or gravel), and admixtures (such as fly ash or silica fume). The proportion of each component in concrete determines its strength, which is referred to as its grade. There are several types of concrete grades used in construction projects, each with its own specific ratio of components.

1. Standard Concrete Grades:

Standard concrete grades are the most commonly used in construction projects, such as building foundations, pavements, and sidewalks. They are classified as C10, C15, C20, C25, C30, C35, C40, C45, C50, and C55. The number next to ‘C’ represents the compressive strength of concrete in megapascals (MPa) when tested after 28 days. For example, C20 concrete will have a compressive strength of 20 MPa after 28 days.

The ratio of components for these grades of concrete is as follows:

– C10 to C15: 1 part cement, 2 parts fine aggregate (sand), and 4 parts coarse aggregate (gravel or crushed stone).

– C20 to C55: 1 part cement, 1.5 to 2 parts fine aggregate, and 3 to 5 parts coarse aggregate.

2. High-Strength Concrete Grades:

High-strength concrete is used for structures that require higher durability and strength, such as high-rise buildings and bridges. The most commonly used high-strength concrete grades are C60, C70, C80, and C90. The ratio of components for these grades varies according to the required strength, but typically, they will have lower water-cement ratios and higher amounts of cement and fine aggregates.

3. Special Concrete Grades:

Special concrete grades are used for specific purposes, such as in extreme weather conditions or in aggressive environments. The most commonly used special concrete grades are:

– Lightweight concrete: This type of concrete is made by replacing the heavier aggregates with lightweight materials, such as expanded clay, shale, or slate. It is commonly used for the construction of precast elements and for thermal insulation.

– Fibre-reinforced concrete: This type of concrete contains fibers, such as steel or synthetic fibers, which improve its toughness, impact resistance, and durability.

– Self-compacting concrete: Self-compacting concrete has a high flowability and can fill in all the spaces in a formwork without the need for vibration. This makes it ideal for construction in congested areas or for structures with complex shapes.

– High-performance concrete: This type of concrete has a high compressive strength (up to 150 MPa), low permeability, and high durability. It is used for specialized structures, such as tunnels, dams, and nuclear power plants.

In conclusion, the selection of the type of concrete grade and its ratio will depend on the intended use and specific project requirements. It is crucial to follow the recommended proportions to ensure the desired strength, durability, and performance of the concrete.

## Different types of concrete grade and their uses

Concrete is a versatile and widely used construction material. It is composed of cement, coarse and fine aggregates, water, and sometimes additives. The strength and durability of concrete are influenced by the type and proportion of its constituents. The grade of concrete is a numerical representation of its compressive strength at 28 days. Different types of concrete grades are used for different purposes based on their strength and durability requirements. In this article, we will discuss the various types of concrete grades and their uses.

1. M5 Grade Concrete

M5 grade concrete has a compressive strength of 5 N/mm2 after 28 days. It is mainly used for leveling, bedding for footings and foundations, and in internal works such as flooring.

2. M7.5 Grade Concrete

M7.5 grade concrete has a compressive strength of 7.5 N/mm2 after 28 days. It is mainly used in non-structural construction like sub-base for walls, lean concrete base, and flooring. It is also used in leveling and bedding for footings and foundations.

3. M10 Grade Concrete

M10 grade concrete has a compressive strength of 10 N/mm2 after 28 days. This is the most commonly used concrete grade for residential construction. It is used in sidewalks, pathways, and reinforced floors.

4. M15 Grade Concrete

M15 grade concrete has a compressive strength of 15 N/mm2 after 28 days. It is used in reinforced concrete structures such as beams, columns, slabs, and foundations. It is also used in making precast elements such as tiles, blocks, and pipes.

5. M20 Grade Concrete

M20 grade concrete has a compressive strength of 20 N/mm2 after 28 days. It is used in non-seismic areas for residential and commercial buildings. It is also used in the construction of pavements, precast elements, and bridge decks.

6. M25 Grade Concrete

M25 grade concrete has a compressive strength of 25 N/mm2 after 28 days. It is commonly used in the construction of heavy-duty structures such as bridges, highways, high-rise buildings, and retaining walls.

7. M30 Grade Concrete

M30 grade concrete has a compressive strength of 30 N/mm2 after 28 days. It is used in the construction of heavy industrial structures, such as long span bridges and high-rise buildings. It is also used in marine structures and offshore platforms.

8. M35 Grade Concrete

M35 grade concrete has a compressive strength of 35 N/mm2 after 28 days. It is mainly used in the construction of high-strength concrete structures such as long span bridges, water tanks, and heavy-duty industrial floors.

9. M40 Grade Concrete

M40 grade concrete has a compressive strength of 40 N/mm2 after 28 days. It is used in the construction of high-rise buildings, bridges, and ultra-heavy-duty industrial structures. It is also used in prestressed concrete structures.

10. M45 Grade Concrete

M45 grade concrete has a compressive strength of 45 N/mm2 after 28 days. It is used in the construction of high-strength and durable structures such as bridge girders, hydraulic structures, and chimneys.

11. M50 Grade Concrete

M50 grade concrete has a compressive strength of 50 N/mm2 after 28 days. It is used in the

## Meaning of C16/20 grade of concrete

C16/20 grade of concrete is a type of concrete that is commonly used in civil engineering projects. It is a standard and widely accepted classification for concrete mixtures, based on its compressive strength at 28 days, which is measured in newtons per square millimeter (N/mm²).

The first number, C16, represents the minimum compressive strength of the concrete in N/mm² after 28 days, while the second number, 20, represents the maximum compressive strength in N/mm² that the concrete is expected to achieve in its lifetime. In other words, this grade of concrete has a minimum strength of 16 N/mm² after 28 days and is expected to achieve a maximum strength of 20 N/mm² over time.

The strength of concrete is an essential consideration in civil engineering projects as it determines the load-bearing capacity of structures. The higher the strength of concrete, the more weight it can bear, and the more durable and long-lasting the structure will be.

C16/20 grade of concrete is considered to be a relatively low strength concrete and is suitable for use in non-structural components such as sidewalks, driveways, and lightly trafficked floors. It is also commonly used in the construction of low-rise buildings such as residential houses, small commercial buildings, and industrial pavements.

This grade of concrete is typically composed of a mixture of cement, coarse aggregates (such as gravel or crushed stone), fine aggregates (such as sand), and water. The proportions of these components are carefully designed and controlled to achieve the desired strength and workability of the concrete.

Apart from its strength, C16/20 grade of concrete also has other desirable properties, including good workability, low shrinkage, and adequate durability. It is also relatively inexpensive, making it a cost-effective option for many construction projects.

In conclusion, C16/20 grade of concrete is a common classification in civil engineering that refers to a concrete mixture with a minimum compressive strength of 16 N/mm² after 28 days and a maximum strength of 20 N/mm² over time. It is suitable for use in non-structural components and low-rise buildings, providing a good balance of strength, workability, and cost-effectiveness.

## C16/20 concrete mix ratio

C16/20 concrete mix ratio is a type of standard strength concrete mix used in construction. It is typically used for structural and non-structural applications such as building foundations, columns, walls, and slabs.

The C16/20 indicates the compressive strength of the concrete after 28 days, which is measured in megapascals (MPa). This type of concrete has a minimum compressive strength of 16 MPa and a maximum compressive strength of 20 MPa.

The mix ratio for C16/20 concrete is 1:2:4, which means that for every 1 part of cement, there are 2 parts of fine aggregate (such as sand) and 4 parts of coarse aggregate (such as gravel). This mix ratio is also known as the “standard mix” and is commonly used in construction due to its strength and durability.

To accurately measure the mix ratio, cement, fine aggregate, and coarse aggregate are usually measured by weight. For example, for every 1 kilogram of cement, there are 2 kilograms of fine aggregate and 4 kilograms of coarse aggregate.

The amount of water used in C16/20 concrete mix should be enough to achieve a workable consistency. The water-cement ratio for this type of concrete is typically between 0.5-0.6, meaning that for every 1 kilogram of cement, 0.5-0.6 liters of water is used.

The slump of C16/20 concrete is usually between 50-75 mm, which means that the concrete has a medium workability and can be easily placed and compacted. This type of concrete can be mixed manually or by using a concrete mixer.

C16/20 concrete has a relatively low strength compared to other standard mixes such as C25/30 or C30/37. However, it is suitable for most general construction works and is cost-effective. It also has good workability and can be easily handled and placed on the construction site.

In conclusion, the C16/20 concrete mix ratio is 1:2:4, with a water-cement ratio of 0.5-0.6, and has a compressive strength of 16-20 MPa after 28 days. It is commonly used in construction for various structural and non-structural components due to its strength, durability, and workability.

## C16/20 concrete composition for 1 cubic metre

C16/20 concrete is a medium strength concrete that is commonly used in construction projects. The “C” in its name stands for “compressive strength” while the numbers after the slash indicate the cylinder compressive strength in megapascals (MPa). Therefore, C16/20 concrete has a compressive strength of 16 MPa after 28 days of curing.

To understand the composition of C16/20 concrete for 1 cubic meter, we need to first look at its basic components:

1. Cement: Cement is the binding agent in concrete and is responsible for its strength. For C16/20 concrete, the recommended cement is Ordinary Portland Cement (OPC) CEM I 42.5N. The amount of cement required for 1 cubic meter of C16/20 concrete is approximately 340 kg.

2. Water: Water is essential for the hydration process of cement. The water-cement ratio is a crucial factor in determining the strength of concrete. Recommended water-cement ratio for C16/20 concrete is 0.55, which means 0.55 kg of water is required for every 1 kg of cement. Therefore, for 1 cubic meter of C16/20 concrete, 187 kg of water is needed.

3. Aggregates: Aggregates are inert materials used in concrete to provide bulk and stability. For C16/20 concrete, the recommended aggregate is a mix of coarse and fine aggregates in a 2:3 ratio. Coarse aggregates such as gravel or crushed stone should have a maximum size of 20 mm, while fine aggregates such as sand should have a maximum size of 5 mm. For 1 cubic meter of concrete, approximately 740 kg of coarse aggregates and 1110 kg of fine aggregates are required.

4. Admixtures: Admixtures are added to concrete to improve its workability, strength, and durability. For C16/20 concrete, water-reducing admixtures are recommended to reduce the water-cement ratio and improve workability. The dosage of admixture is typically 0.4% to 1% by weight of cement. For our 1 cubic meter of concrete, the required amount of admixture would be 3.4 kg to 3.4 kg, depending on the desired strength and workability.

Once we have all the required components, we can calculate the composition of C16/20 concrete for 1 cubic meter using the following formula:

Cement = (340/1000) x 1 = 0.340 m³ = 340 kg

Water = (0.55 x 340) = 187 kg

Coarse aggregates = (740/1000) x 1 = 0.740 m³ = 740 kg

Fine aggregates = (1110/1000) x 1 = 1.110 m³ = 1,110 kg

Admixture = (0.4% x 340) = 1.36 kg or (1% x 340) = 3.4 kg

Therefore, the composition of C16/20 concrete for 1 cubic meter would be:

• Cement – 340 kg

• Water – 187 kg

• Coarse aggregates – 740 kg

• Fine aggregates – 1,110 kg

• Admixture – 1.36 kg to 3.4 kg

## Meaning of C12/15 grade of concrete

C12/15 grade of concrete refers to a type of concrete that has a compressive strength of 12 N/mm² after 28 days of curing. It is commonly used in general construction projects where the load-bearing requirements are not very high. The “C” in the grade signifies its compressive strength, while the numbers after the slash represent the characteristic cylinder strength and cube strength respectively, in N/mm².

The C12/15 grade of concrete is considered to be of low strength and is typically used in the construction of non-load-bearing walls, paths, driveways, and other minor structures. It is also commonly used as a base for lighter structures such as garden sheds, small garages, and agricultural buildings. Due to its low strength, it is not suitable for heavy or multi-story construction.

The main components of C12/15 grade concrete are cement, sand, and coarse aggregates such as gravel or crushed stone. The water-to-cement ratio used in this grade of concrete must be carefully controlled to ensure a strong and durable mix. The typical proportions for this grade of concrete are 1:2:4, with one part cement, two parts sand, and four parts coarse aggregate.

C12/15 grade of concrete has a relatively low cement content, making it more economical and cost-effective compared to higher grade concrete. It also has a higher water-to-cement ratio, which makes it easier to work with and pour. However, this also means that it has a lower density, which can result in a less durable and more porous finished product.

To ensure the quality and strength of C12/15 grade concrete, proper curing is crucial. Curing refers to the process of keeping the concrete moist and at a moderate temperature for an extended period. This allows the concrete to gain strength and become more durable. Failure to properly cure the concrete may result in cracking or a decrease in strength.

In summary, the C12/15 grade of concrete is a low-strength concrete that is commonly used in general construction projects. It is suitable for non-load-bearing structures and can be more cost-effective compared to higher grade concrete. However, careful proportioning and proper curing are essential for achieving a strong and durable finished product.

## C12/15 concrete mix ratio

C12/15 concrete mix ratio refers to the ratio of the components used in making concrete, namely cement, sand, and coarse aggregates (stones). This ratio is expressed in terms of the compressive strength of the concrete after 28 days of curing. In this case, the compressive strength is expected to be 12 MPa (megapascals) at 28 days.

The C12/15 mix ratio is classified as a standard strength concrete and is commonly used for building foundations, low-rise structures, pavements, and other structural elements that do not require high strength. This mix is suitable for non-structural applications where strength is not the primary factor but rather its workability and cost-effectiveness.

The C12/15 mix ratio consists of 1 part cement, 2 parts sand, and 4 parts coarse aggregates. This ratio is based on volume and not weight, which means that for every 1 unit of cement, 2 units of sand, and 4 units of coarse aggregates are used.

The type of cement used in this mix is usually Ordinary Portland Cement (OPC) of grade 32.5 or 42.5. OPC is the most commonly used cement type in construction and provides the necessary binding properties for the concrete.

The sand used in the mix should be clean, free from any organic or clay materials, and have a maximum particle size of 5mm. The coarse aggregates, on the other hand, should have a maximum size of 20mm and be of good quality to ensure the strength and durability of the concrete.

The C12/15 mix ratio is considered to have a medium workability, which means it can be easily molded, compacted, and finished using basic construction tools. The water-cement ratio for this mix is usually between 0.4-0.6, which is the amount of water needed to create a chemical reaction with the cement and ensure proper hydration.

It is important to note that the C12/15 mix ratio can be adjusted slightly depending on the specific needs of the project. For example, if a higher strength is required, the amount of cement can be increased, or if the concrete needs to be more workable, the amount of water can be increased. However, any adjustments should be done carefully and with the guidance of a professional to ensure the overall quality and strength of the concrete.

In conclusion, the C12/15 concrete mix ratio is a standard strength mix commonly used for various non-structural applications. Its mix of 1:2:4 cement, sand, and coarse aggregates provides a cost-effective and workable concrete that can adequately support light to medium load-bearing structures.

## C12/15 concrete composition for 1 cubic metre

C12/15 concrete is a type of concrete that falls under the C12 category in the European standard EN 206-1. This standard defines the different strength classes of concrete and is widely used in the construction industry in Europe. In this article, we will discuss the composition of C12/15 concrete for 1 cubic metre.

The composition of C12/15 concrete is typically made up of a combination of cement, water, aggregate, and additives. The strength class C12 indicates that this type of concrete has a characteristic compressive strength of 12 MPa (megapascals), while the number 15 represents the maximum size of aggregate used, which is 15 millimetres.

The following is the general composition of C12/15 concrete for 1 cubic metre:

1. Cement – The amount of cement used in C12/15 concrete is usually around 350 kg/m3. Cement is the binding agent that holds the concrete mixture together and provides strength to the final product.

2. Water – The amount of water used in C12/15 concrete is typically around 175 liters/m3. Water is necessary for the hydration process of cement and to make the concrete workable. It is important to note that the water-cement ratio should be carefully controlled as an excessive amount of water may weaken the concrete.

3. Aggregate – The aggregate used in C12/15 concrete is a combination of coarse and fine aggregates. Coarse aggregates are typically gravel or crushed stone, while fine aggregates are usually sand. The overall aggregate content for 1 cubic metre of C12/15 concrete is around 1300 kg/m3.

4. Additives – Additives such as air-entraining agents, water-reducing agents, and superplasticizers may be added to modify the properties of C12/15 concrete. These additives can improve workability, increase strength, or reduce the amount of water needed in the mixture.

The mixing ratio of C12/15 concrete is generally 1 part cement: 2 parts water: 3 parts aggregate. However, this may vary depending on the specific project and the manufacturer’s recommendations.

In conclusion, C12/15 concrete is a commonly used type of concrete in construction with a compressive strength of 12 MPa and a maximum aggregate size of 15 mm. It is important to carefully follow the recommended composition and mixing ratios to achieve the desired strength and durability of the concrete.

## Conclusion

In conclusion, knowing the different types of concrete grade and their corresponding ratios according to British Standard (BS) is crucial in ensuring the quality and durability of our concrete structures. With the right knowledge and application of these ratios, we can achieve the desired strength, workability, and durability of our concrete mixtures. It is important to always refer to the BS guidelines and test the concrete properties to achieve the best results. By following these standards and ratios, we can build safer and more resilient structures that can withstand various environmental conditions. Let us continue to adhere to these standards and constantly improve our understanding of concrete to ensure the long-term success of our construction projects.