Batching of concrete for small site?


    ๐Ÿ‘‰What is batching of concrete? 

Batching of concrete means measuring different ingredients of concrete (i.e. cement, sand, coarse aggregate and water) before mixing it. When this measurement is done on the basis of volume, we call it Volume Batching.

    ๐Ÿ‘‰What is a small batching plant?

Small batching plant is suitable for places that require extreme mobility. There are two models available which are powered by electric motors and there is one model powered by diesel engine. There are total of three bins for addition of sand, cement and aggregates. All the bins are with individual load cells for accurate weighing.

Methods of Batching Concrete

1. Volume Batching

  • In volume batching, materials are measured on the basis of volume. It is less precise method of batching
  • Measurement boxes or gauge boxes of known volume are used to measure materials.
  • Cement is taken in the form of bags, where volume of one bag of cement (50 kg) is taken as 35 liters.
  • Volume of Gauge box used is made equal to the volume of one bag of cement which is 35 liters or multiple thereof.
  • Gauge boxes are generally deeper and contains narrow top surface and they are made of timber or steel or iron.
  • Volumes of different sized fine aggregate and coarse aggregate are measured individually by these gauge boxes.
  • Water is measured using water meter or water cans of known volume are used.
  • To make 1:1:2 ratio concrete mix according to volume batching, one should take one bag of cement (35 liters) , 1 gauge box of fine aggregate (35 liters) and 2 gauge boxes of fine aggregate (70 liters). If the water-cement ratio is 0.5, then half of the volume of cement which is 25 liters of water should be taken.

 

2. Weight Batching

  • In this method, Materials are measured on the basis of weight. It is accurate method of batching.
  • Weigh batchers or other types of weighing equipment are used to measure weight of materials.
  • Cement, fine aggregate, coarse aggregate and water are taken by weighing.
  • Weigh batchers used are available in two types namely mechanical weigh batcher and electronic weigh batchers.
  • In mechanical weigh batchers, weights are measured using spring and dial gauge arrangement and it is widely used equipment in weigh batching.
  • In electronic weigh batchers, electronic scales and load cells supported by hoppers are used to measure the weight of ingredients of concrete.
  • Weigh batchers available are may be Manual or semi-automatic or fully automatic . Manual type is used for small concrete production job while other two types are used for large concrete production.
  • In case of semi-automatic weigh batching, aggregate container gates are lifted manually and it is automatically closed after reaching required quantity in the weighing machine.
  • In fully automatic weigh batcher, all the process will be done automatically. The benefit of this type equipment is, it also measures the moisture content present in the aggregate and corrects the required quantity of water-cement with respect to moisture content of aggregates.
  • To prepare 1:1:2 concrete mix using weigh batching, measured quantity of materials are 50 kg of cement, 50 kg of fine aggregate and 100 kg of coarse aggregate.

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