Reattività agli alcali di aggregati: prova in calcestruzzo - Alkali-reactivity of aggregates: concrete prism expansion test

Alkali-aggregate reaction is an expansive phenomenon that may deleteriously affect concrete. Its prevention in new concrete structures depends on the appropriate selection of materials and this is, in turn, dependent on the knowledge of alkali reactivity of the aggregates. Among the various test methods available for assessing the alkali reactivity of aggregates, the concrete prism expansion test at 38°C and high humidity level, which lasts one year, is the most reliable. The standard procedures for this test are reported in UNI 11604, which was recently revised for the purpose of a better specification of the grain size of test aggregate, and for giving acceptance criteria of the final test result. More details in this article.