Effect of high-temperature on the microstructure of alkali-activated binder

Publication date: Available online 25 January 2020Source: Materials Today: ProceedingsAuthor(s): Kruthi Kiran Ramagiri, Arkamitra KarAbstractThe current scenario of construction industry highlights the need for development of sustainable construction materials that provide properties comparable to portland cement (PC). Alkali-activated binder (AAB) produced by alkaline activation of aluminosilicate-rich industrial wastes, like fly ash and slag is one such potential alternative to PC which substantially reduces the embodied energy of concrete and solves the problem of industrial wastes disposal. However, the practical usage of AAB is limited owing to the complexity in optimizing the mix. The performance of AAB is influenced by several parameters, type and composition of activators, proportion and composition of the precursors, and curing conditions. Previous research on AAB substantiate its high-temperature stability compared to PC. The specimen-level performance of AAB can be well estimated from its microstructural changes. However, there is limited research reported on the mechanism contributing to the enhanced high- temperature stability of blended-AAB. The present study aims to investigate comprehensively the microstructural evolution of fly ash/slag-based AAB when exposed to high-temperatures. Three AAB mixes with varying fly ash: slag ratio (100:0, 70:30 and 50:50) are exposed to four different temperatures (ambient, 538 °C, 760 °C and 892 °C). The microstructur...
Source: Materials Today: Proceedings - Category: Materials Science Source Type: research