In this batching method, two units of measurements are employed: liquids are measured in litres and solids in cubic metres. That is all ingredients, viz., water, cement, sand and coarse aggregates are measured in litres, while the end-product concrete is measured in cubic metres.
In volume batching, other quantities are measured keeping cement as the base. Considering that 1 litre of cement equals 1.44 kg, a bag of 50 kg cement has a volume of 3.5 litres. Hence, for measuring aggregates wooden boxes of an inner volume of 3.5 litres has to be used. A size of box of 40 cm × 35 cm × 25 cm satisfies this 3.5 litre volume requirement. Handles are provided on the sides for handling.
As the density of water is 1 g/ml, it can be measured by weight or by volume. The quantity of water required depends on the water–cement ratio. Thus, for a water–cement ratio of 0.50 the quantity of water required is 25 litres (0.50 × 50 = 25 litres).
For accurate batching, the moisture content and absorption of aggregates and bulking of sand have to be ascertained.
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