Calculation of water cement ratio in concrete mix

This construction video tutorial is very useful for civil engineering students to learn how to work out the ratios of water and cement in concrete work.

The water–cement ratio refers to the proportion of the weight of water to the weight of cement utilized in a concrete mix. A lesser ratio results in providing superior strength and stability, but may transform the mix problematic to deal with and build. Adaptability is maintained by applying plasticizers or super-plasticizers.

If the amount of water in a concrete mix is more, the cement paste will be more diluted. This will impact the compressive strength as well as the tensile and flexural strengths, the porosity, the shrinkage and the color.

It is recommended to apply a maximum .50 water to cement ratio as soon as concrete is uncovered to freezing and thawing in a moist condition or to deicing chemicals with adherence to the 1997 Uniform Building Code.

It is recommended to apply a maximum .45 water to cement ratio for concrete with extreme or very extreme sulfate conditions with adherence to the 1997 Uniform Building Code.

Water permeability improves significantly when there is a water cement ratio in excess of .50.

Strength gets better with lower water cement ratios. A .45 water cement ratio potentially will hit 4500 psi (pounds per square inch) or more. A .50 water cement ratio potentially will attain 4000 psi or more.

Video Source: Civil Engineers