Experimental investigation on the ferrosialate geopolymer mortar and concrete

Abstract

The idea of waste utilization along with finding a sustainable alternative material newlinefor cement-based concrete to reduce global emissions inspired the research. The influence newlineof various parameters on the strength of the ferrosialate/ Red mud (RM)-based newlinegeopolymer mortar specimens in compression are considered and compared that with newlinesialate/conventional Fly ash (FA)-based geopolymers. Two models, GEP- (I and II) are newlinesimulated using Gene Expression Programming (GEP). Using these generated models, newlinemathematical equations are derived to predict the strength in compression for the ferrosialate newlineand the sialate geopolymers. For the maximum strength gain, red mud content newlinein the ferrosialate geopolymer binder should not be greater than 30% of the binder for newlinethe oven-cured regime and similarly it is 35% for the ambient- curing regime, correspondingly. newlineEight molar of the sodium hydroxide solution is recommended for the ferrosialate newlinebinders for its maximum performance. The oven-cured regime has a greater newlineopportunity to acquire the strength than the ambient-cured regime. The thermal behaviour newlinestudies revealed that the strength increase in the sample is noted for both sialate newlineand ferrosialate samples until 400 _C exposure. Considerable depletion in strength newlineof the specimens is detected only after subjecting them to 600 degree (Celsius). Ferrosialate newlinesamples showed 28.8%, 37.1%, and 30.4% higher residual strength than sialate newlinesamples after their exposure to highly acidic, sulphate and chloride environments, respectively. newlineSamples with 20% red mud content showed greater resistance to all the newlinethree chemical environments. Therefore, considering the long-term performance of the newlinebinder, red mud content should not be more than 20% in the binder. Tests on concrete newlinesamples revealed that ferrosialate concrete samples displayed 80.42% and 231% higher newlinecompressive and split tensile strength than sialate samples, respectively. Ferrosialate newlinegeopolymers out-performed the sialate geopolymers in both strength and durability aspects. newline