Effects of agro-industrial by-products as alumina-silicate source on the mechanical and thermal properties of fly ash based-alkali activated binder

Abstract

The construction industry has a potential to incorporate various agro-industrial waste for development of sustainable construction materials which will eventually results in a cleaner and healthy environment. This research emphasizes on incorporation of agro-industrial wastes such as Rice husk ash (RHA), fly ash (FA), copper slag (CS), bottom ash (BA) and glass powder (GP) to develop ecofriendly alkali-activated blocks. The research studies the effect of blending alumina-silica rich agro-industrial byproduct with fly ash and the influence of resulting oxide ratios on the thermal, mechanical and physical properties of the proposed binder. The experimental study indicates that the combination of CS with FA resulted in the highest strength of 63 MPa among all the combinations. However, the NaOH molar ratio also plays a crucial role in performance of alkali activated block as all the mixes having 12 M NaOH resulted in higher mechanical performance. The findings suggest that the raw materials, curing temperature and NaOH concentration also contribute towards strength development apart from the oxide ratios like Si/Al, Na/Al and Na/Si. Finally, a comparative performance analysis amongst the agro-industrial waste (used in current study) as an ingredient to develop alkali activated binder was provided.