Role of water/cement ratio on strength development of cement mortar

The effect of water/cement (w/c) ratio on the mechanical properties such as compressive strength and split tensile strength of cement mortar cylinders and cubes was investigated experimentally for 28 days curing period as per IS standard. Based upon the experimental results, empirical equations have been developed to predict the strength of cement mortar mixes with various w/c ratios. It is observed that Abrams' law is applicable for the cement mortar also. The cement mortar contains varying proportions of portland pozzolana cement (PPC) and river sand such as 1:3, 1:4, 1:5, 1:6, 1:7, 1:8 with different w/c ratios. An empirical equation has been developed between split tensile strength and compressive strength of cement mortar. Results show that compressive strength and split tensile strength of cement mortar decreased with an increase in the w/c ratio. It is observed that minimum w/c ratio required to make the cement mortar workable is 0.5.