Akademik Veri Yönetim Sistemi
European Journal of Environmental and Civil Engineering, cilt.30, sa.1, 2026 (SCI-Expanded, Scopus)
In this study, the effects of alkali-silica reaction (ASR) on different geopolymer mortar and concrete specimens were compared. For this purpose, fly ash, ground granulated blast furnace slag, and metakaolin were mixed with non-reactive limestone aggregate and reactive quartz aggregate to produce non-reactive and reactive mortars and concretes. Due to the lack of availability of geopolymer standards, ASTM C1260 and ASTM C1293 standards were followed to apply ASR exposure to mortar and concrete specimens, respectively. Ultrasonic pulse velocity, compressive strength, flexural strength, capillary water absorption, and ASR tests were conducted on a macro-scale, while SEM and EDS tests were performed on a micro-scale. The results revealed that enormous expansion and significant ASR cracks were observed up to 56 days due to an aggressive environment affecting fly ash-based mortars, while fly ash-based concretes exhibited the lowest expansion. Contrary to Portland cement, the ASR environment of mortars had favourable effects on the mechanical strength results. Based on the results, modifications to the curing condition and period are necessary for the evaluation of ASR tests on geopolymer mortars according to the ASTM C1260 standard, and the ASR test period for geopolymer concrete is recommended to be increased to at least 2 or 3 years.