Water cement ratio is the ratio of the weight of water to the weight of cement used to prepare 1 unit of concrete. It is essentially the weight ratio and not the volume.

The water/cement ratio primarily governs the strength of concrete. More water added to make concrete higher will be the w/c ratio and the lesser will be the strength.

These facts were first studied in 1918 AD by Abrams. Abrams also told that the relation between the Water/Cement ratio and strength is not linear.

## Following is a method to calculate water/cement ratio

If 2 bag of cement is used to prepare some random amount of concrete and for that 60 liters of water is consumed then the calculation is as below.

*The weight of cement used to prepare concrete is – 100 kg*

*The weight of water used to prepare concrete is – 60 kg [as 60 liters water is used]*

**W/c = 60/100 = 0.6 **

The Water cement ratio has no dimension as it is a weight to weight ratio.

Following is an image giving an idea about the water/cement ratio and strength as per IS-10262:2019.

Related Readings

Types of Cement, and their properties and applications

**Soundness test on cement as per Indian Standard**

**Most widely use admixtures use for concrete**