Investigation of Flow Times of Geopolymer Grouts

warming. In this context, it is known that cement production contributes approximately 7% to global CO2emissions. Increased construction activity is driving up cement consumption, highlighting the need forsustainable, environmentally friendly alternative binding materials. Geopolymers are binding materials obtainedby chemically activating waste materials containing silicate and aluminate with suitable alkali activators and canbe considered as an alternative to Portland cement (PC). Studies in the literature show that geopolymers providehigh strength, durability, and acid resistance under suitable conditions. In this study, geopolymer-based groutmixtures were prepared using waste materials such as fly ash (FA) and silica fume (SF) and evaluated as analternative to cement. In the study, geopolymer grout mixtures containing cement, FA, SF, and alkali activatorsolution (NaOH and Na2SiO3) (AAS) at different water/binder ratios (w/b = 0.85, 1.05, and 1.25) were prepared,and their flowability performance was determined using the Marsh funnel test. The experiments were conductedin accordance with the American Society for Testing and Materials (ASTM) D6910/D6910M-19 standard. Theresults showed that increasing the w/b ratio reduced the viscosity of the grout mixtures and decreased the flowtime. Additionally, it was determined that FA and SF additives positively affect fluidity. The flow times ofmixtures containing AAS were found to be lower than those of mixtures containing only cement. The addition ofAAS enhances the effectiveness of geopolymerization, enabling the grouts to acquire suitable fluidity propertiesfor injection.