Everything You Need to Know About Batching of Concrete

Concrete is a strong and durable material that is made by the combination of cement, aggregates and water. The process of combining the required amount of ingredients based on their volume or mass, for the production of perfect concrete for a construction is known as Batching of concrete. Once the concrete is produced with perfect quality, it is then transferred to a transit mixer. In this article let’s discover the importance of batching concrete and its methods. Keep reading!

What is Batching of Concrete?

Batching, in simple terms, means skilfully mixing the required ingredients like cement, fine and coarse aggregates and, water,. in an accurate measure to form the best quality of concrete. Materials used for mixing are measured by  their volume or weight in proportion to prepare good quality concrete. Strong concrete can increase the stability of a construction by eradicating structural issues and  Leakage. Batching of concrete can speed up the construction work and  reduce the wastage of materials used for concrete. Once the required homogeneous mix  is produced through batching, it is then used for construction  purposes in buildings, pavements, bridges, etc.

Types of Batching Concrete

It is important to make a uniform concrete mix as it plays a vital role in the durability of any construction. There are three types of batching of concrete usually done before concrete pouring . They are, 

• Random Volumetric Batching  
• Volume Batching
• Weight Batching

Let’s have a brief glance at  these types. 

Random Volumetric Batching.

A process in which the concrete ingredients do not have fixed proportions or quantites is called Random Volumetric Batching. The ingredients are quantified and mixed based on rough estimations of workers. It can result in failure due to its lack of estimated strength. This method is definitely unscientific and inconvenient for any construction project and is strictly not recommendable. 

Volume Batching.

Volume batching of concrete is executed with the aid of measurement boxes. These measurement boxes are termed ‘farmas’ or ‘gauge boxes’ that are used to measure the concrete materials. Gauge boxes are made out of timber, steel or iron.  It is deeper downwards and has a narrow top. This method is a bit less precise or accurate. Materials used for Volume Batching are measured under the terms of volume. If the volume of one cement bag which is around 50kg (35 liters) is taken, then the volume of Gauge or farmas is equal to the volume of cement, without overfill. Gauge boxes are then used to measure and proportion the aggregate components. For example, to achieve 1:1:2 ratio, one farma of cement, one farma of sand and 2 farmas of aggregates are mixed together. The quantity of water is measured by water cans with fixed volume or by water meter. 

Weight Batching.

In weight batching, the concrete ingredients are taken in fixed proportions  with the help of ‘weight batchers’ or other weighing instruments. This method is more accurate, simple and flexible than volume batching. There are different types of weight batching: 

Manual batching: Here, all solid ingredients are weighed manually. It can be used for minor and small jobs.

• Semi-automatic weight batching: Here, the machine gates for weighing are opened manually with operated switches, and then the gates are automatically closed immediately when the material poured has reached the required weight. 
• Fully automatic batching concrete: It has automatic microprocessor-controlled batching systems which. It measures the components automatically in perfect proportions.

According to the varied needs and availability, one of these types of weight batching is used. Sometimes, when it comes to big projects, people use automatic batching plants to achieve the desired quality and consistency.

Materials like cement, fine aggregate, coarse aggregate and water are taken by weighing. Water plays a major role, so the essential amount of water must be available. Lack of water leads to weak and unworkable concrete whereas excess water will destroy the strength of concrete. Poor batching cannot give a homogeneous concrete mix so, the workability will deteriorate. Thus, it is important to have skilled workers while handling the procedure for better outcomes.

Factors Affecting the Choice of Batching system.

There are various factors that can affect the choice of the batching system, such as: .

• Job size: The method of batching depends on the size of the project. Larger projects can opt for automatic weighing systems, while manual weighing works well for small projects
• Concrete production rate: When project timelines are small, concrete mixing and production has to be done quickly and may require automatic weighed batching. 
• Labour availability: When there is a lack of labour, automatically weighed batching can be opted for.
• Cost: Manual weighing for batching can be opted for when there are budget constraints, as automatic weighing costs more.

Conclusion.

Batching of concrete is the most important method for mixing and estimating the needed concrete materials for construction. Once the mix is ready, it is transferred to the transit mixer to create a homogeneous and quality mixture. Poor batching can result in leakages and loss of strength in the concrete It can lead to porous concrete, which will lead to corrosion and can literally reduce the life of the construction. This  can double your investment since the cost of repair is high. Traditional batching is done by volume batching which is not very precise. Batching accuracy is important as it aids in obtaining the desired outcome. It is  better to do weight batching instead of volume batching. Before making a concrete mixture, it is important to note whether the concrete material is proper and accurate in proportion to achieve good  quality. 

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