The amount of water added to concrete during the mixing process is called mixing water, which is calculated based on the water cement ratio in the mix proportion (referring to the weight ratio of water to cement in concrete).
Mixing water consists of two parts, one part is compound water and the other part is free water.
Compound water is necessary for the hydration of cement, and sufficient compound water is needed to ensure the full hydrolysis and hydration of cement particles, the formation of crystals and setting.
However, this part of the water consumption is relatively small, generally only accounting for a quarter of the mixing water.
The remaining water is called free water, which is added to meet operational requirements, such as ensuring the workability and slump of concrete.
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