The relationship of curing methods and curing temperatures with NaOH molarity and their effects on the behavior of geopolymer concrete

This study investigates the mechanical performance of geopolymer concrete cured under various oven temperatures and ambient conditions, focusing on the interactions among curing regimes, alkaline activator molarities, and ground granulated blast furnace slag (GGBFS) incorporation. In this context, the effects of variable parameters of curing types (ambient and oven) and temperature between 45 °C and 120 °C, molarity beween 8 M and 12 M, and GGBFS content between 5% and 20% on compressive, flexural, and tensile strength were investigated in the experimental program. The oven-cured samples contained no GGBFS and were cured at 45 °C, 60 °C, 90 °C, and 120 °C, whereas the ambient-cured mixes incorporated different GGBFS ratios. The findings revealed that the mechanical properties of GPC were significantly affected by both NaOH concentration and curing regime. The highest performance under oven curing was achieved with 12 M NaOH and 90 °C, while under ambient curing the highest performance was achieved by the mixture containing 12 M NaOH and 10% GGBFS. Although the samples cured under ambient conditions generally exhibited lower strength, this method has significant potential with an appropriate mixture design and offers a more sustainable alternative more energy-efficient. This study makes a significant contribution to establishing a balance between performance and environmental impacts in GPC design.