Using chemical model system to simulate alkali-silica reaction : why and how

Known as the “concrete cancer”, alkali-silica reaction (ASR) has attracted academie and industrial interests since its first report in the 1940s. The mechanism of ASR governing the reaction process and the consequent deterioration of concrete structure is one of the most popular research topics due to its scientific and industrial signiftcance. Due to the heterogeneousness of concrete, however, it is extremely difficult to explore the fundamental mechanism and eventually, conclude a reliable and practical guidance for the mitigation of ASR by studying an in situ concrete. In consideration of limiting the heterogeneousness of concrete, therefore, a Chemical model system can be used for simulating the physico-chemical interactions between the reactive silica present in aggregates and various constituents of cement paste. In this work, the necessity of creating a Chemical model system to simulate alkali-silica reaction under laboratory conditions from a Chemical point of view is given. Many Chemical model systems ifom the previous studies are reviewed. Critical factors which need to be considered during the creation of the model system are discussed to provide practical suggestions.