Fly Ash Based Geopolymer Mortar - Carbonation and Microstructural Performance

Abstract

Concrete is the construction material of highest exigency which, in turn, created a huge demand for ordinary Portland cement as a binder. Regrettably, its current production process is highly energy intensive, and at elevated temperature, when Calcination of Limestones takes place, it liberates embodied anthropogenic CO2 polluting the environment. Not only that, but it is also user-hostile and comparatively costly too. Therefore, construction industries looking at concrete research sectors to invent new, environmentally- compassionate durable, sustainable and cheap construction and binding materials instead of present ones. Nowadays, Geopolymer binders and composites are synthesized by activating alkali solution with Silica and Alumina rich pozzolanic material such as Fly ash, have emerged out as a brilliant substitute to conventional binders and composites through the process of Geopolymerization. The objective of the present study is to investigate the performance of Fly ash based geopolymer mortar in whereby there is 100% substitution of cement by Fly ash, i.e., the absolute absence of cement. The present study has examined the mix composition parameters comprise Sodium hydroxide concentration and aggregate to binder ratio, whereas process parameter included curing temperature. Also, the Carbonation tests were conducted along with microstructure investigations viz., X-Ray Diffractometry (XRD) and Scanning Electron Microscopy (SEM).