The aim of this study was to determine of the potential alkali-silica reactivity of the aggregates obtained from Harşit River valley. In the first chapter of the thesis, alkali-silica reaction is detailed, the effects of mineral and chemical admixtures on the alkali-silica reaction is described and the experimental methods used in the determination of the reaction are discussed. The second chapter, experimental work is given. Samples were obtained from the aggregate quarries located in Harşit river valley. The reactivity of aggregate are examined according to TS 2517 chemical method, ASTM C 1260 accelerated mortar bar method and petrographic analysis. As a result, the aggregate obtained from Harşit River may considered to be potentially alkali silica reactive. To be more conclusive, it could be suggested to make concrete prisms tests and perform experimental work using mineral additives to control the ASR, if needed.
Key Words: Aggregate, Alkali-Silica reaction, petrografic analysis, ASTM C289 Chemical Method and ASTM C1260 accelerated mortar bar.