Akademik Veri Yönetim Sistemi
Iranian Journal of Science and Technology - Transactions of Civil Engineering, cilt.48, sa.5, ss.3559-3572, 2024 (SCI-Expanded)
Various industrial wastes and natural resources are used as precursors in the production of geopolymers, which are known to be more environmentally friendly compared to Portland cement. In this study, kaolin, which is a natural resource, and Fly ash (FA), which is an industrial waste, were used as precursors. In this study, the influence of FA substitution in the kaolin-based geopolymer was investigated. Geopolymer mortar mixtures were produced by replacing of kaolin with C Class FA at 10%, 20%, and 30% by weight of kaolin. Geopolymer samples were produced using NaOH for activation. Unit weight, flexural and compressive strengths, ultrasound pulse velocity (UPV) tests and X-ray diffraction (XRD), Scanning electron microscope (SEM), and Fourier transform infrared spectroscopy (FTIR) analyses were applied on the samples. It has been observed that the replacement of FA in kaolin enhances the physical properties and improves the mechanical properties of mortar. Moreover, it was observed that the strength of the samples increased with the increase of the activator ratio and activation temperature. The addition of up to 30% FA has the potential to incessantly improve the strength of the mortars at all curing temperatures. Additional crystalline phases except kaolinite, zeolite, quartz, albite, and, mullite were not detected on the XRD with the addition of FA. In addition, unactivated kaolin, surface-activated particles, and geopolymeric gel formations were observed in the SEM images. As a result of this study, it was determined that the use of kaolin and FA together is appropriate in the production of geopolymer.