Thermal analysis for concrete incorporated with different nano, micro and recycled materials

This research aims to investigate the impact of employing various types of materials as partial cement replacements on the characteristics of high-strength concrete. As cement replacements, Nano SiO2, Nano CaCO3, micro SiO2, micro CaCO3, recycled silica gel (beads and powder), and limestone were employed, as well as binary combinations of (Nano SiO2+Nano CaCO3), (micro CaCO3+micro SiO2), and (recycled silica gel powder+limestone). In addition to the control mix, ten sets of concrete mixes were created with progressive cement replacement. Thermal analysis (TG-Thermogravimetric) and (DTG-Derivative Thermogravimetry) were employed to determine the CH content of each concrete group. The nano-silica mix had the lowest calcium hydroxide (CH) content, followed by the binary nano mix and crushed silica gel mix. In contrast, the other mixes had approximate values. Still, they were all less than the control mix, indicating that larger amounts of calcium silicate hydrate (CSH) gel formed after replacement, which has primarily contributed to improving the strength and durability of concrete.