Performance of Cement Mortar Mixtures Containing Fine Aggregate and Admixtures

The purpose of this study is to investigate the influence of the cement/sand (c/s) ratio on the behavior of cement mortar. The used c/s ratios in this study were 1:0, 1:0.45, and 1:0.83. The findings of this study showed that increasing the sand content reduces the compressive strength of the mortar mixture by 41.5 and 28.2% for the c/s ratios of 1:0.45, and 1:0.83, compared to the plain cement mortar (c/s: 1:0). The increase in sand content requires more water content to increase the workability and strength of the mixtures. However, the flexural strength slightly increased compared to the control mortar. In addition, to enhance sustainability, the cement was replaced with two waste industrial materials namely, micro silica (MS) and fume treatment plant (FTP) dust by 20% of cement weight. The modified mixtures (c/s: 1:0) also showed reduced strength at the testing age. The compressive strength of the modified mixtures was reduced by 50% and 19% for the FTP and MS-modified mixtures, respectively. On the other hand, the flexural strength was reduced by 19.1 and 30.2% for the FTP and MS-modified mixtures. This reduction can help achieve certain strength requirements by lowering the cement content in cement concrete mixtures.