A good quality concrete-mix design provides the foundation for a long-lasting infrastructure. Concrete-mix design involves a process of preparation in which a mix of ingredients creates the necessary strength and durability for the concrete structure. All the ingredients in the concrete blend have different properties. An excellent combination of concrete requires expertise and experienced concrete-mix specialists. RMS Ready-mix specialists test all components to ensure their physical properties and the capacity of the project location. The tested ingredients are water, coarse aggregate, sand, chemicals, cement, soil and reinforcement. 

The values of the physical properties are measured after the test for concrete-mix design considerations; it will ensure the strength of the structure and prevent failure of the mix. However, ingredients vary for the concrete mix from one project to another, so it is essential to test the physical properties of the required materials as per the location and environment. 

Read on to learn the importance of concrete-mix design for your construction project.

Condition Of Design 

Concrete-mix design must achieve specific requirements, but materials' physical properties might vary from location to location. Manufacturers practice producing a trial concrete-mix design with soil rock, water, and cement and considering weather conditions. It will help them know if the concrete leads to structural failure. The nature of parent material changes from region to region and country to country. Therefore, there must be a design analysis at any location considering the specific area. The alteration or modification must be made in the material's physical properties for the concrete-mix design as per the need. 

Selection Of Design

Modern concrete design is complex, and the choice of a concrete mix will depend on the need of the project in terms of strength, appearance and local legislation. 

The manufacturer determines the requirements of the concrete mix by considering the weather conditions the concrete is exposed to and the required design strength. The standard cured cylinder samples help determine the compressive strength of concrete. 

Many factors affect the making of concrete, such as the cost of various additives and aggregates, to the trade-offs between the slump for easy mixing, placement and performance. Concrete-mix is designed using cement, coarse and fine aggregates, water and chemical admixtures. The mixing method is specified by the conditions in which it is used.

All these allow users of the concrete to be confident that the structure will perform adequately. Various types of concrete are developed for unique applications. Concrete mixes are also designed using software programmes, allowing users to select the preferred mix design method and customised concrete.

Types Of Concrete-Mix

There are two primary types of concrete-mix

1. Regular Concrete

The term used for concrete is produced by following the mixing instructions that are usually published on the packets of cement. It uses sand and other common material, such as aggregate, and it gets mixed in improvised containers. The ingredients in the concrete mix depend on the nature of the application. Regular concrete can withstand pressure from about 10 MPs to 40 MPs with light-duty uses. Many types of pre-mixed concrete are available, including powered cement mixed with an aggregate that only needs water for the mixing process.

1. High-strength Concrete

Concrete with a compressive strength will class higher than C50/60. In the UK, BS EN 206-1 (British standard for concrete) defines the strength of concrete. The main objective of high-performance concrete is to reduce weight and improve the structure's durability. Compared to the regular concrete mix, high-strength concrete is in a plastic or semi-fluid state when mixed so that it is easier to mould. 

High-strength concrete has high cement content and is often sticky and hard to handle and place. However, the cement will not bleed.

Factors Affecting The Concrete-Mix Design 

• Grade Designation 

Each concrete grade has its strength in N/mm2 when subject to test after 28 days of curing with any curing medium. It could be water, jute bags with water and sand with water. The choice of concrete grade depends on the types of members it is used for. There are some standard concrete grade ratios, and it is re-organised as a trial mix design to achieve the design strength. Most concrete ratios are rated in kilograms by weight and concreted to the equivalent proportion by volume. 

• Choice Of Cement

Ordinary Portland Cement is readily available for building structures and is most commonly used for trial mix design. For marine systems, sulphate resistance and rapid hardening portland cement are most adopted for trial mix design. For regular water logged-in area structures, sulphate resistance portland cement is used for trial mix design. However, all cement types should undergo physical test analysis to provide the best performance. 

• Choice Of Aggregate Size

All aggregates are not suitable for concrete. Some aggregates may contain certain minerals that are harmful, and some may not have the required properties needed for concrete design. Some may have high slit and clay content at high percentages that are not allowed in concrete. Both fine and coarse aggregates must be of quality size following the UK standard requirement to control the quality of the concrete mix.

• Types Of Water

Any water is subjected to testing before use. It should range within the requirement of water. Mostly, all consumable water is suitable for concrete work, as specified by BS 3148 (methods to test water for making concrete).

• Water To Cement Ratio

Water to cement ratio is necessary to achieve the required consistency, initial setting, final setting and soundness of the cement concerning workability. The compacting factor and slump of the designed concrete accomplish the desired outcome. However, it is subjected to cement tests and concrete trial mix design analysis. 

• Quality Control 

The degree of control is estimated statistically by the variations in test results. The variation in strength results from the difference in the properties of the mixed ingredients and lack of control in accuracy in batching, mixing, placing, curing and testing. The factor controlling this difference is known as quality control. 

• Workability 

When working conditions change, the properties of desired concrete also change. Concrete is easily placed without segregation, and most minor compaction is considered good concrete. 

• Durability  

It measures the required strength of any concrete grade after 28 days of curing the concrete. It defines the age and stability of the concrete's life span; this is always achieved after the trial mix design of the required grade of concrete. The concrete's control test analysis is also carried out during the creation of the concrete mix application to find the required strength on-site for safety and durability. 

The Relationship Between Design And Construction 

The design and construction of the structure are directly related. A design's strength, safety, and durability are achieved through good craftsmanship and quality control at a construction site. However, good craftsmanship and quality control are only possible if the specifications are clearly defined. In the current practices, concrete design is conceived in computer files and graphics by applying the provisions of codes and standards and physically created at the site using these files and graphics.

Conclusion 

RMS Concrete follows the standard rules while mixing the concrete. Our BSI 9001 specialists are certified to select the accurate proportions of the materials as per the project's requirements. They guide you to have the perfect ready-mix concrete. If durability and excellent quality are what you are looking for in a concrete mix, then you have arrived at the right place! Call us on +44 808 274 0949 for your questions about mixtures, or visit us online to learn more about our services.