Optimization of mechanical characteristics of cement mortar incorporating hybrid nano-sustainable powders

Abstract

Abstract This research examines the impact of using hybrid nano-sustainable materials such as nano-silica and nano-slag, at three designated contents (2, 4, and 6%) by the cement weight. Mechanical and physical characteristics were studied at 7 and 28 ages. Overall, the experimental results showed the positive impacts of used hybrid nano-sustainable additives on fresh and hardened properties of modified cement mortar. The compressive strength of mortar containing nano-slag with 2, 4, and 6% enhanced as 11, 33, and 32% at 28 days, respectively, and correspondingly, direct tensile strength enhanced as 16, 39, and 30% at 28 days, respectively. Furthermore, the compressive strength of cement mortar containing 2, 4, and 6% of nano-silica improved by 20, 44, and 59% at 28 days, respectively. Besides direct tensile strength improved by 19, 37, and 46% at 28 days, respectively, as compared with reference cement mortar. The 4% nano-slag and the 6% nano-silica showed the optimum results of improvements of the compressive strength and direct tensile strength as 33 and 39% and 59 and 46% at 28 days, respectively. Hence, the optimization results of selected cement mortar comprising hybrid nano-sustainable materials as 6 wt% nano-silica and 4 wt% nano-slag produce a greater enhancement of mortar strength. Compressive and direct tensile strength improved by 73 and 53% at 28 days, respectively.